Scriptures the church fathers reference on the subject of Purgatory:

Genesis 2:23-24 “So the Lord God sent him away from the luxurious garden to work the earth from which he was taken. So he threw Adam out and settled him opposite the luxurious garden [i.e Paradise] and stationed the cherubim and the flaming, turning sword to guard the way to the tree of life.” (Lexham Septuagint)

Deuteronomy 4:24 “For the Lord your God is a consuming fire, a jealous God.”

Isaiah 1:24-25 “On account of this, this is what the Lord, the master, Sabaoth says: “Woe to you who have power over Israel, for my wrath will not cease among the opponents, and I will execute fair judgment from my enemies. And I will bring my hand upon you and burn you into something clean; and I will destroy those who resist, and I will take all lawbreakers away from you.” (Lexham Septuagint)

Isaiah 1:25  “And I will bring my hand upon you, and purge you completely.” (Brenton)

Isaiah 4:4 “The Lord will wash out the filth of the sons and daughters of Zion, and he will purge the blood from the middle of them by a spirit of judgment and a spirit of burning.” (Lexham)

Isaiah 6:5-7 “And I said, Woe is me, for I am pricked to the heart; for being a man, and having unclean lips, I dwell in the midst of a people having unclean lips; and I have seen with mine eyes the King, the Lord of hosts. And there was sent to me one of the seraphs, and he had in his hand a coal, which he had taken off the altar with the tongs: and he touched my mouth, and said, Behold, this has touched thy lips, and will take away thine iniquities, and will purge off thy sins.”

• Psalm 119:1-4 (Brenton) “In mine affliction I cried to the Lord, and he hearkened to me.  Deliver my soul, O Lord, from unjust lips, and from a deceitful tongue. What should be given to thee, and what should be added to thee, for thy crafty tongue? 4 Sharpened weapons of the mighty, with coals of the desert.”

Isaiah 10:16-17 “Rather, Lord Sabaoth will send dishonor on your honor, and burning fire will burn on your glory. And the light of Israel will become a fire, and it will sanctify him with a burning fire, and it will consume the wood like hay.” (Lexham Septuagint)

• Isaiah 10:16-17 “but the Lord of hosts shall send dishonour upon thine honour, and burning fire shall be kindled upon thy glory. And the light of Israel shall be for a fire, and he shall sanctify him with burning fire, and it shall devour the wood as grass.” (Brenton)

Isaiah 47:14-15 “Behold, they all shall be burnt up as sticks in the fire; neither shall they at all deliver their life from the flame. Because thou hast coals of fire, sit thou upon them; these shall be thy help.” (Brenton)

Isaiah 50:11 “Look! You are all kindling a fire and feeding a flame; walk in the light of your fire and in the flame that you have kindled. These things have happened to you because of me; you will sleep in sorrow.”

Daniel 7:9-10  “I continued to watch until when thrones were set up and the ancient of days was seated, who had a robe just like snow, and the hair of his head was like pure white wool. His throne was like a flame of fire, his wheels a burning fire. A river of fire was drawing, and there proceeded down according to the face of him a river of fire. Thousands of thousands were attending to him, and innumerable myriads attended to him, and a judgment seat was set, and the books were opened.” (Lexham Septuagint)

Malachi 3:2-3 “But who will endure the day of His entrance, or who will stand in His appearance? Because He enters as a fire of a furnace and as a kind of cleansing. He will sit, smelting and cleansing, as if it were silver and as if it were gold; and he will purify the children of Levi and pour them out just like gold and like silver, and they will become those who bring to the Lord a sacrifice in righteousness.” (Lexham)

Zechariah 13:8-9 “And it will be in all the earth,” says the Lord. “Two of its parts will be utterly destroyed and come to an end, but the third part will be spared in it. And I will carry over the third part through fire, and I will make them red-hot like silver tried by fire, and I will test them like gold that has been tested. He will call on my name, and I will hear him, and I will say, ‘This is my people,’ and he will say, ‘The Lord is my God.’” (Lexham)

Matthew 5:25-26 “Agree with your adversary quickly, while you are on the way with him, lest your adversary deliver you to the judge, the judge hand you over to the officer, and you be thrown into prison. Assuredly, I say to you, you will by no means get out of there till you have paid the last penny.”

Matthew 12:31-32 “Therefore I say to you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven men. Anyone who speaks a word against the Son of Man, it will be forgiven him; but whoever speaks against the Holy Spirit, it will not be forgiven him, either in this age or in the age to come.”

Luke 3:16-17 “John answered, saying to all, “I indeed baptize you with water; but One mightier than I is coming, whose sandal strap I am not worthy to loose. He will baptize you with the Holy Spirit and fire. His winnowing fan is in His hand, and He will thoroughly clean out His threshing floor, and gather the wheat into His barn; but the chaff He will burn with unquenchable fire.”

1 Corinthians 3:11-15 “For no other foundation can anyone lay than that which is laid, which is Jesus Christ. Now if anyone builds on this foundation with gold, silver, precious stones, wood, hay, straw, each one’s work will become clear; for the Day will declare it, because it will be revealed by fire; and the fire will test each one’s work, of what sort it is. If anyone’s work which he has built on it endures, he will receive a reward. If anyone’s work is burned, he will suffer loss; but he himself will be saved, yet so as through fire.”

Hebrews 12:29 “For our God is a consuming fire.”

‭‭2 Maccabees‬ ‭12‬:‭39‬-‭45‬ “On the next day, as by that time it had become necessary, Judas and his men went to take up the bodies of the fallen and to bring them back to lie with their kinsmen in the sepulchres of their fathers. Then under the tunic of every one of the dead they found sacred tokens of the idols of Jamnia, which the law forbids the Jews to wear. And it became clear to all that this was why these men had fallen. So they all blessed the ways of the Lord, the righteous Judge, who reveals the things that are hidden; and they turned to prayer, beseeching that the sin which had been committed might be wholly blotted out. And the noble Judas exhorted the people to keep themselves free from sin, for they had seen with their own eyes what had happened because of the sin of those who had fallen. He also took up a collection, man by man, to the amount of two thousand drachmas of silver, and sent it to Jerusalem to provide for a sin offering. In doing this he acted very well and honorably, taking account of the resurrection. For if he were not expecting that those who had fallen would rise again, it would have been superfluous and foolish to pray for the dead. But if he was looking to the splendid reward that is laid up for those who fall asleep in godliness, it was a holy and pious thought. Therefore he made atonement for the dead, that they might be delivered from their sin.”

Ante-Nicene 

Apostle Peter (In the Recognitions of Clement)

Origen

Tertullian

Clement of Alexandria 

The Shepherd of Hermas 

Felicity and Perpetua

Cyprian 

Apostolic Constitutions

Post-Nicene (325-700 AD)

Augustine

Ambrose

Basil

Hilary of Poitier

Jerome

John Chrysostom 

Gregory the great

Cyril of Jerusalem 

Ambrosiaster

Theodore of Heraclea

Gregory of Nyssa

Epiphanius

Caesarius of Arles

Isidore of Seville

Bede

Church fathers:

Peter:

After he had said this, I (Clement) replied: “If those whom His coming finds righteous will enjoy the kingdom of Christ, then will those who died before His coming be completely deprived of the kingdom?” Then Peter said: “You compel me, O Clement, to reveal some things that are beyond human speech. Yet, as far as it is permitted to speak of them, I will not refuse. Christ, who was from the beginning and always has been, was present in every generation to the righteous — though secretly, yet always — especially to those who were expecting Him, and to them He often appeared. But the time had not yet come for the resurrection of those whose bodies had been dissolved. Rather, this was seen as a kind of reward from God: that whoever was found righteous might remain longer in the body, or at least — as it is clearly written about a certain righteous man in the Law — that God took him. In the same way it was also done with others who pleased His will: they were taken up into Paradise and preserved for the kingdom. But those who were unable to fulfill the rule of righteousness completely, yet had some remnants of wickedness in their flesh, had their bodies dissolved, while their souls were kept in good and joyful regions, so that at the resurrection of the dead, when they receive their bodies again, they — now purified by that very dissolution — may obtain an eternal inheritance for the good they had done. And therefore, blessed are all who will obtain the kingdom of Christ, for they will not only escape the torments of Hell, but will also remain incorruptible, and they will be the first to see God the Father and will receive among the first the order of honor before God. — Recognitions of Clement, Book 1, chapter 52

[This may or may not be a reference to Purgatory, hard to determine]

Therefore he insinuates into your minds opinions of gods of whatsoever kinds, only that he may withdraw you from the faith of one God knowing that your sin is his comfort. For he, for his wickedness, was condemned from the beginning to eat dust, for that he caused to be again resolved into dust him who had been taken from the dust, even till the time when your souls shall be restored, being brought through the fire; as we shall instruct you more fully at another time. — Apostle Peter, Recognitions of Clement, Book 5, chapter 17

Truly they know not that the counsels of God are not like men’s counsels; for, in the first place, He knows the thoughts of all men, and all must give an account not only of their actions, but also of their thoughts. And their sin is much less who strive to understand well and fall, than that of those who do not at all strive after good things. Because it has pleased God that he who errs in his knowledge of good, as men count errors, should be saved after being slightly punished. But they who have taken no care at all to know the better way, even though they may have done countless other good deeds, if they have not stood in the service He has Himself appointed, come under the charge of indifference, and are severely punished, and utterly destroyed. – Apostle Peter, Clementine Homilies, Homily 7

Hermas:

….But I, shameless as I yet was, asked her, “Is repentance possible for all those stones which have been cast away and did not fit into the building of the tower, and will they yet have a place in this tower?” “Repentance,” said she, “is yet possible, but in this tower they cannot find a suitable place. But in another and much inferior place they will be laid, and that, too, only when they have been tortured and completed the days of their sins. And on this account will they be transferred, because they have partaken of the righteous Word. And then only will they be removed from their punishments when the thought of repenting of the evil deeds which they have done has come into their hearts. But if it does not come into their hearts, they will not be saved, on account of the hardness of their heart.” – The Shepherd of Hermas 1.3.7 (90 AD)

I said to him, “Sir, explain this also to me.” “What is it you ask?” he said. “Whether, sir,” I continued, “they who indulge in luxury, and who are deceived, are tortured for the same period of time that they have indulged in luxury and deceit?” He said to me, “They are tortured in the same manner.” [“They are tormented much less, sir”, I replied; ] “for those who are so luxurious and who forget God ought to be tortured seven-fold.” He said to me “You are foolish, and do not understand the power of torment. Why, sir,” I said, “if I had understood it, I would not have asked you to show me.” “Hear,” he said, “the power of both. The time of luxury and deceit is one hour; but the hour of torment is equivalent to thirty days. If, accordingly, a man indulge in luxury for one day, and be deceived and be tortured for one day, the day of his torture is equivalent to a whole year. For all the days of luxury, therefore, there are as many years of torture to be undergone. You see, then, he continued, that the time of luxury and deceit is very short, but that of punishment and torture long.” – The Shepherd of Hermas 3.6.4 (90 AD)

“Explain to me a little further, sir,” I said. “What is it that you desire?” he asked. “Why, sir,” I said, “did these stones ascend out of the pit, and be applied to the building of the tower, after having borne these spirits? “They were obliged,” he answered, “to ascend through water in order that they might be made alive; for, unless they laid aside the deadness of their life, they could not in any other way enter into the kingdom of God. Accordingly, those also who fell asleep received the seal of the Son of God. For,” he continued, “before a man bears the name of the Son of God s he is dead; but when he receives the seal he lays aside his deadness, and obtains life. The seal, then, is the water: they descend into the water dead, and they arise alive. And to them, accordingly, was this seal preached, and they made use of it that they might enter into the kingdom of God.” “Why, sir,” I asked, “did the forty stones also ascend with them out of the pit, having already received the seal?” “Because,” he said, “these apostles and teachers who preached the name of the Son of God, after falling asleep in the power and faith of the Son of God, preached it not only to those who were asleep, but themselves also gave them the seal of the preaching. Accordingly they descended with them into the water, and again ascended. [But these descended alive and rose up again alive; whereas they who had previously fallen asleep descended dead, but rose up again alive.] By these, then, were they quickened and made to know the name of the Son of God. For this reason also did they ascend with them, and were fitted along with them into the building of the tower, and, untouched by the chisel, were built in along with them. For they slept in righteousness and in great purity, but only they had not this seal. You have accordingly the explanation of these also.” – The Shepherd of Hermas, Parable 9, Chapter 16

Acts of Paul and Thecla

[Not written by anybody who knew Paul. Tertullian says: “But the woman of pertness, who has usurped the power to teach, will of course not give birth for herself likewise to a right of baptizing, unless some new beast shall arise like the former; so that, just as the one abolished baptism, so some other should in her own right confer it! But if the writings which wrongly go under Paul’s name, claim Thecla’s example as a licence for women’s teaching and baptizing, let them know that, in Asia, the presbyter who composed that writing, as if he were augmenting Paul’s fame from his own store, after being convicted, and confessing that he had done it from love of Paul, was removed from his office. “ (On Baptism, 17) Although this book taught error about women baptizing, this book still reflects the teachings of the Church on prayer for the dead and why we pray for the dead.]

“And after the exhibition, Tryphaena again receives her. For her daughter Falconilla had died, and said to her in a dream: Mother, thou shaft have this stranger Thecla in my place, in order that she may pray concerning me, and that I may be transferred to the place of the just.” Acts of Paul and Thecla (160 A.D.), ANF,VIII:490

Abercius:

“…These things I, Abercius, having been a witness [of them] told to be written here. Verily I was passing through my seventy-second year. He that discerneth these things, every fellow-believer [namely], let him pray for Abercius. And no one shall put another grave over my grave.” – Inscription of Abercius, (About 190 AD) 

Clement of Alexandria:

Accordingly the believer, through great discipline, divesting himself of the passions, passes to the mansion which is better than the former one, that is, to the greatest torment, taking with him the characteristic of repentance from the sin she has committed after baptism. He is tortured then still more — not yet or not quite attaining what he sees others to have acquired. Besides, he is also ashamed of his transgressions. The greatest torments, indeed, are assigned to the believer. For God’s righteousness is good, and His goodness is righteous. And though the punishments cease in the course of the completion of the expiation and purification of each one, yet those have very great and permanent grief who are found worthy of the other fold, on account of not being along with those that have been glorified through righteousness. – Clement of Alexandria, The Stromata 6.14

Tertullian:

Moreover, as often as the soul has fallen short as a defaulter in sin, it has to be recalled to existence, until it “pays the utmost farthing,” Matthew 5:26 thrust out from time to time into the prison of the body. To this effect does he tamper with the whole of that allegory of the Lord which is extremely clear and simple in its meaning, and ought to be from the first understood in its plain and natural sense. Thus our adversary (therein mentioned ) is the heathen man, who is walking with us along the same road of life which is common to him and ourselves. Now “we must needs go out of the world,” 1 Corinthians 5:10 if it be not allowed us to have conversation with them. He bids us, therefore, show a kindly disposition to such a man. “Love your enemies,” says He, “pray for them that curse you,” Luke 6:27 lest such a man in any transaction of business be irritated by any unjust conduct of yours, and “deliver you to the judge” of his own (nation Matthew 5:25), and you be thrown into prison, and be detained in its close and narrow cell until you have liquidated all your debt against him. Then, again, should you be disposed to apply the term “adversary” to the devil, you are advised by the (Lord’s) injunction, “while you are in the way with him,” to make even with him such a compact as may be deemed compatible with the requirements of your true faith. Now the compact you have made respecting him is to renounce him, and his pomp, and his angels. Such is your agreement in this matter. Now the friendly understanding you will have to carry out must arise from your observance of the compact: you must never think of getting back any of the things which you have abjured, and have restored to him, lest he should summon you as a fraudulent man, and a transgressor of your agreement, before God the Judge (for in this light do we read of him, in another passage, as “the accuser of the brethren,” Revelation 12:10 or saints, where reference is made to the actual practice of legal prosecution); and lest this Judge deliver you over to the angel who is to execute the sentence, and he commit you to the prison of hell, out of which there will be no dismissal until the smallest even of your delinquencies be paid off in the period before the resurrection. What can be a more fitting sense than this? What a truer interpretation? – Tertullian, A Treatise On the Soul, chapter 35 (210 A.D.)

“All souls, therefore; are shut up within Hades: do you admit this? (It is true, whether) you say yes or no: moreover, there are already experienced there punishments and consolations; and there you have a poor man and a rich…Moreover, the soul executes not all its operations with the ministration of the flesh; for the judgment of God pursues even simple cogitations and the merest volitions. ‘Whosoever looketh on a woman to lust after her, hath committed adultery with her already in his heart.’ Therefore, even for this cause it is most fitting that the soul, without at all waiting for the flesh, should be punished for what it has done without the partnership of the flesh. So, on the same principle, in return for the pious and kindly thoughts in which it shared not the help of the flesh, shall it without the flesh receive its consolation. In short, inasmuch as we understand ‘the prison’ pointed out in the Gospel to be Hades, and as we also interpret ‘the uttermost farthing’ to mean the very smallest offence which has to be recompensed there before the resurrection, no one will hesitate to believe that the soul undergoes in Hades some compensatory discipline, without prejudice to the full process of the resurrection, when the recompense will be administered through the flesh besides.” – Tertullian, A Treatise on the Soul chapter 58 (210 A.D.)

Indeed, she prays for his soul [i.e her husband], and meanwhile asks refreshment for him, and desires fellowship with him in the first resurrection, and makes offerings on the anniversary days of his falling asleep. – Tertullian, On Monogamy, chapter 10 (210 AD)

And how long are we going to keep sawing back and forth over this line—clinging to an observance so old that its very age has given it authority? If no Scripture has laid it down, custom has surely confirmed it, and that custom without a doubt has flowed from tradition. For how could anything ever come into use unless it was first handed down? You say that even when something is defended as tradition, written authority must still be demanded. Well then, let us ask whether tradition itself, if it is not written, ought to be rejected. Clearly we would have to deny that it should be accepted—if we weren’t already bound by the precedents of other observances that we uphold without any written document, solely on the basis of tradition, and then defend under the authority of custom. To start with baptism: when we approach the water, right there—indeed, even a little earlier in the church under the hand of the bishop—we declare that we renounce the devil, his pomp, and his angels. Then we are dipped three times, giving more answers than the Lord specified in the Gospel. Afterwards, when we have come up, we taste beforehand the harmony of milk and honey; and from that day we refrain from daily bathing for the whole week. We take the sacrament of the Eucharist—commanded by the Lord for all and celebrated even before dawn—not from anyone’s hand but that of the presiding ministers. We make offerings for the dead and on the anniversaries of their birth into eternal life. On the Lord’s Day we think it wrong to fast or to pray while kneeling. The same freedom from fasting we enjoy from Easter to Pentecost. We even shudder if a crumb of our bread or a drop of our cup falls to the ground. And at every step or movement—on our way in or out, when putting on shoes, washing, sitting at table, lighting lamps, lying down, or sitting anywhere—we trace the sign of the cross upon our forehead. … If you demand a law from the Scriptures for these and other such practices, you’ll find none. Tradition will be shown to you as their author, custom as their confirmer, and faith as their keeper. The reasoning behind this tradition, custom, and faith you can either see for yourself or learn from someone who has; in the meantime, believe at least that there is some reason, and that it deserves your obedience. … By these examples it is shown that even an unwritten tradition can be defended by its observance, confirmed by long-standing custom, and proven genuine by its continued practice. In fact, even in civil life, custom is accepted as law when the law is silent. It makes no difference whether it stands by writing or by reason, since reason itself commends the law. And if law rests on reason, then whatever is established by sound reason—whoever formulates it—has the force of law. Do you not think that every believer has the right to conceive and establish something, provided it accords with God, advances discipline, and promotes salvation, since the Lord said, “Why do you not judge for yourselves what is right?” (Luke 12:57). And this applies not only to judgments but to all matters requiring discernment. The Apostle also says, “If in anything you are ignorant, God will reveal it to you” (Philippians 3:15), for he himself was accustomed to give counsel when he had no command from the Lord, and to issue some things from himself—yet being guided by the Spirit of God, who leads into all truth. Therefore his counsel and instruction, being supported by divine reason, already have the weight of a divine command. So, if you now demand such reasoning—without rejecting the role of tradition, whoever may have handed it down—do not look at the person, but at the authority, and above all at the authority of custom itself, which must be respected lest it cease to be the interpreter of reason. And if God has indeed given this reason, then you will understand that custom, too, must be observed. — Tertullian, The Chaplet chapter 3-4 (211 AD.)

Acts of the Martyrdom of Felicity and Perpetua:

“I saw a vision of Dinocrates going out from a gloomy place, where also there were several others.  He was parched and very thirsty, with a filthy countenance and pallid color; the wound on his face that he had when he died.  This Dinocrates had been my brother after the flesh, seven years of age, who died miserably with disease.  For him I had made my prayer; and between him and me there was a large interval, so that neither of us could approach to the other.   And I knew that my brother was in suffering, but I trusted that my prayer would bring help to his suffering; and I prayed for him every day until we passed over into the prison of the camp, for we were to fight in a camp show.   Then I made my prayer for my brother day and night, groaning and weeping, that he might be granted to me.  Then, on the day that we remained in fetters, this was shown to me:  I saw that that place which I had formerly observed to be in gloom was now bright; and Dinocrates, with a clean body, well clad, was finding refreshment.  He went away from the water to play joyously, after the manner of children; and I woke from this vision.   Then I understood that he was translated from the place of punishment.” – Acts of the Martyrdom of Felicity and Perpetua, Chapters 2, (203 AD)

Origen:

“It is good, then, not to have a sword of sin, but, next best, having one, is not to brandish it, but to make it stay idle. For something surprising comes about from not brandishing the sword of sin; it does not just rust and grow dull, but even wears down, for when the sword of sin is idle, it finally disappears. For it is appointed by the Lord for sin to disappear. If, then, we are blessed by not engaging in sin or brandishing the sword from its sheath, we shall destroy the sin and have no need of fire, of the chastisement of darkness, of those things in a threat as being laid up for those who have lived badly. But if we do not hear monitory and healing words, it is apparent that fire remains for us, so that we may come to the fire where every work is proved. For, as regards each work, the fire will prove what sort of thing it is. “If someone’s work remains after being tested, he will receive a reward,” and so on (so as not to repeat the whole passage). 1 Corinthians 3:13-14 Should Paul go to the fire, nonetheless, Paul will hear, “If you go through fire, the flame shall not consume you.” Isaiah 43:2 Should Peter come to the fire, nonetheless the fire will not touch him. But should there be any sinner, he goes like Paul and Peter to the fire, but he does not pass through the fire as Paul and Peter do.” Origen, Homilies on Psalms, Psalm 36, Homily 3

“For I baptize you in water, but he who comes after me is greater than I. He will baptize you in the Holy Spirit and in fire.'” Luke 3:16-17 When does Jesus baptize “with the Holy Spirit”? And again, when does he baptize “with fire”? Does he baptize at one and the same time “with Spirit and fire,” or at distinct and different times? He says, “But you will be baptized with the Holy Spirit not many days hence.” After his ascension into heaven, the apostles were baptized “with the Holy Spirit.” But Scripture does not record that they were baptized “with fire.” At the Jordan river, John awaited those who came for baptism. Some he rejected, saying, “generation of vipers,” and so on. But those who confessed their faults and sins he received. In the same way, the Lord Jesus Christ will stand in the river of fire near the “flaming sword”, Genesis 3:24 if anyone desires to pass over to paradise after departing this life, and needs cleansing, Christ will baptize him in this river and send him across to the place he longs for. But whoever does not have the sign of earlier baptisms, him Christ will not baptize in the fiery bath. For, it is fitting that one should be baptized first in “water and the Spirit.” Then, when he comes to the fiery river, he can show that he preserved the bathing in water and the Spirit. Then he will deserve to receive in addition the baptism in Christ Jesus, to whom is glory and power for ages of ages. Amen. – Origen, Homilies on Luke 24.1-2

But the end brings distress to all, and even those who are blessed, whether they come from Israel or even from the Gentiles, in the present age the word of evangelical doctrine purifies, so that they might be like those to whom the Lord was saying, “Behold you are already clean on account of the word that I have spoken to you.” John 15:3 But whoever should spurn the purification of the Word of God and of evangelical doctrine reserves himself for sorrows and penal purifications, when the fire of Gehenna purifies with torments the one whom neither apostolic doctrine nor the evangelical word have purified, according to what is written, “And I will purify you with fire leading to purity.” Isaiah 1:25 But for how long a time and how many ages this purging, which is applied by means of penal fire, exacts torments from sinners only he is able to know to whom “the Father gave all judgment.” – Origen, Commentary on Romans 8.12.8

The text wants you to make a more daring assertion if your hearing still would follow. What is the “sacrifice” which is offered “for sin” and is “very holy” except “the only begotten Son of God,” Jesus Christ my Lord? He alone is the “sacrifice for sins” and he is “a very holy offering.” But since it added that “the priest who offers it will eat it,” Leviticus 6:19 it seems to be hard to understand. For that which it says must be eaten seems to be referring to the sin; just as in another place the prophet says concerning the priests that “they will eat the sins of my people.” Hosea 4:8 Whence this also shows that the priest ought to eat the sin of the one who is offering. We frequently show from Holy Scripture that Christ is also the sacrifice which is offered for the sin of the world and the priest who brings the offering. The Apostle explains this by one word when he says, “Who offered himself to God.” Hebrews 9:14 Therefore, this is the priest who eats and consumes “the sins of the people,” about whom it is said, ”You are a priest forever after the order of Melchizedech.” Psalm 109:4 Therefore, my Lord and Savior eats “the sins of the people.” How does he eat the sins of the people? Hear what is written: “Our God is a consuming fire.” Deuteronomy 4:24 What does the “God of fire” consume? Will we be so senseless as to think that “God” consumes “the firewood” or “straw” or “hay”? 1 Corinthians 3:12 But the “God of fire” consumes human sins. He consumes them, devours them, purges them, as he says in another place, “I will purge you with fire for purity.” Isaiah 1:25 This is “to eat his sin,” who offers a sacrifice “for sin.” For “he took our sins” and in himself he eats them and consumes them as if a fire. Thus, on the other hand, those who remain in sin, “death” is said “to have swallowed” them, as it is written, “Death, which prevails, will swallow.” Psalm 48:15 – Origen, Homilies on Leviticus 5.3.2

It says, “And he will take a censor filled with coals.”(Lev.16.12) Not all are cleansed by this fire which is taken “from the altar.” Aaron is cleansed by that fire, so is Isaiah, and any who are like them. But others who are not of this kind, among whom I also reckon myself, shall be cleansed by another fire. I fear it is the one about which it was written, “A river of fire was flowing before him.” Daniel 7:9-10 This “fire” is not “from the altar.” The fire that is “from the altar” is the fire of the Lord. But that which is outside the altar is not of the Lord but is properly of each one who sins, about whom it said, “Their worm will not die, and their fire will not be extinguished.” Isaiah 66:24 Therefore, this “fire” is of those who have ignited it just as it also was written in another place, “Walk in your fire and in the flame which you kindled for yourselves.” Isaiah 50:11 But to Isaiah his own fire was not applied but the fire of the altar which “will cleanse his lips” and for the person about whom it is said, ”And he will take up a censor filled with coals of fire from the altar that is before the Lord and he will fill his hands with finely composed incense.” Indeed, our Lord did that more fully. For “he filled his hands with fine incense” about which it was written, “Let my prayer be directed as incense in your sight.” Origen, Homilies on Leviticus 9.8.1

The nature of sin is like the material which is consumed by fire, which the Apostle Paul says is built upon by sinners who “upon the foundation” of Christ “build wood, hay and straw.” 1 Corinthians 3:12  In this it is shown openly that there are certain sins so light that they are compared “to straw,” on which the fire, when brought, cannot last long; but that there are others like “hay” which the fire also consumes easily, but which lasts a little longer than “the straw.” But there are others which are compared to “wood” in which, by the nature of the faults, the fire may find lasting and great fuel. Thus, therefore, each sin by its nature and extent pays its due penalties. However, what need is there for the faithful and those who know God to think about the qualities of the penalties? What need is there “to place wood,” “hay,” or even “straw” ”upon the foundation” of Christ? For why “do we not place upon” the precious “foundation” rather “gold” or “silver” or “precious stones,” which when the fire approaches near it may find nothing to consume? For if it should come near “straw,” from “the straw” it will produce coals and ashes; but if it should come near “gold” it will yield purer “gold.” We would say these things for those who neglect to stop the habit of cursing from their mouths; who although they do not curse from the heart, although they do not pronounce curses by desire and hostile intent, they nevertheless commit uncleanness of lips and impurities of the mouth according to the word of Isaiah. (6:5) – Origen, Homilies on Leviticus 14.3.2

“Our God is a consuming fire.” Heb. 12.29. What does this fire consume? Not wood that we can observe, not hay that is perceptible, not straw that can be seen; rather, “if you build upon the foundation of Jesus Christ with…wood”—that is, sinful deeds; “with hay”—that is, sinful deeds; or “with straw” 1 Cor. 3.12. — that is, lesser sinful deeds—then this fire comes and tests all those things. What is this fire, which the Law proclaims, and about which the Gospel is not silent? “The fire will test the work of each one, [to see] of what sort it is.” 1 Cor. 3.13. What is this fire, O Apostle, which tests our works? What is this fire so wise that it preserves my gold, that it displays my silver more brilliantly, that it leaves intact that precious stone which is within me, that it consumes only the evil things I have done—the wood, the hay, and the straw which I have built upon [the foundation of Jesus Christ]. What is this fire? “I have come to send fire upon the earth, and how I wish that it may be kindled!” Jesus Christ said, “How I wish that it were already kindled” Lk. 12.49. —because he is good, and he knows that if this fire is kindled, wickedness will be consumed. It is written in the prophets, “He sanctified him in a blazing fire, and devoured [his] forest like hay”; Isa. 10.17 and again, “The Lord of Hosts will send forth reproaches for your honor, and for your glory a blazing fire will be kindled” Isa. 10.16.  — that is to say, so that you may be glorified, a fire is sent forth into your sinful deeds. Do you wish to learn from the prophet also that the torments of the good God have been established for the benefit of those who undergo them? Listen to the same prophet when he says, “You have coals of fire; you will sit upon them. These will be a help to you.” Isa. 47.14-15 (LXX) – Origen, Homilies on Ezekiel 1.3.3-4

“And a brightness round about it,” then “a fire shining brightly, and in the midst of it, as it were the appearance of electrum.” Ezek. 1.4. God takes away the bad things from us in two ways: by Spirit and by fire. If we are good, and focused on his instructions, and are being educated by his words, he takes away our evils by the Spirit, according to that which is written, “But if by the Spirit you put to death the deeds of the flesh, you will live.” Rom. 8.13. But if the Spirit has taken away the evils from us, then we need the purification of the fire. …. For we must be melted “like gold in a furnace,” Wisdom 3.6. and like electrum, with a most powerful fire. And in this very prophet whom I am now explaining, you have a reference to the Lord sitting in the midst of Jerusalem and melting those who have been mixed with silver, tin, bronze, and lead—and with a reproachful voice criticizing those who have in themselves a mixture of baser material: “You have become mixed silver; and you have become worthless silver, like the seed from a grape.” Ezek. 22.18-23 For when we introduce vices and passions coming from our evils into the creation of God, which was good from the beginning, then we are mixing bronze, tin, and lead with silver and gold, and fire is needed for purifying them. And so, we must carefully exercise foresight, so that when we come to that fire, we will pass through it safely, and like gold and silver and precious stones that have no trace of adulteration, we will be not so much burned as proved by the flames. – Origen, Homilies on Ezekiel 1.13

…(2) Therefore, the divine Word, rebuking certain presbyters of this kind, says to the prophet: “Those men”—that is, the aforementioned presbyters—“have focused their own thoughts in their own hearts, and they have placed the punishment of their own iniquities before their own faces.” Ezek. 14.3. Let none of us think that torturous pains are inflicted on us by anyone other than ourselves. God does not create punishments; rather, we ourselves prepare in advance for ourselves what we suffer. And so, now again I shall make opportune use of that [Scriptural] testimony which I have used frequently in the past: “Walk in the light of your own fire, and in the flame which you kindled.” Isa. 50.11. The fire belongs to no one but yourselves—you who have piled up wood and straw —material for the conflagration to come. – Origen, Homilies on Ezekiel 3.7.2

Those who pursue the study of medicine say that for some kinds of surgical remedies, not only cutting but also burning is applied. To those whose [flesh] is decaying from a long-lasting cancer they apply the glowing-hot blade of a sharp knife or some sort of very sharp iron implement, so that the roots of the cancer may be eliminated by the heat, while by the incision, the decayed flesh will be cut off and a passageway for the introduction of medicines will lie open. Who among us, in your opinion, has a sin similar to a cancer, so to speak, such that neither the simple iron blade nor the fire’s burning alone will be enough, but instead, both must be applied, so that he is burned and cut? Listen to the Savior indicating the system of fire and iron, in two passages. In the one passage, he says, “I have not come to send peace upon the earth, but a sword,” Mt. 10.34 but in the other, “I have come to send fire upon the earth, and would that it were already burning!” Lk. 12.49. So then, the Savior brings both sword and fire, and he baptizes you with both sword and fire. For he baptizes with fire those who have not been healed by the baptism of the Holy Spirit, because they were not able to be cleansed [or ‘purged’] by the purification of the Holy Spirit. – Origen, Homilies on Ezekiel 5.1.2

(3) Thus there is a lye Word and a soap Word which, when it has been spoken, purifies that sort of filth. But since the Word which is lye and the Word which is soap does not cure every kind of sin, and there are sins which need neither lye nor soap, it is said to him who thinks that he has sins which can be washed away in lye and soap: “Even if you wash in lye and cover yourself with soap, you are yet stained in your iniquities before me,” says the Lord. And just as certain wounds are cured by emollients and others by oil and others need a bandage and hence are healed, yet others are wounds about which it is written: It is not closed with ointments or oil or bandages; but your country is a desert, your cities are burnt up, Isaiah 1:6-7 LXX so there are certain sins which foul the soul, and man needs for such sins the lye of the Word, the soap of the Word, yet there are some sins which are not cured in this way, for they are not comparable to filth. (4) Accordingly, when one has understood the differences in sins, see how the Lord says in Isaiah, The Lord will wash away the filth of the sons and daughters of Zion, and will cleanse the blood from their midst by a spirit of judgment and a spirit of burning. Isaiah 4:4 Filth and blood; filth by a spirit of judgment, blood by a spirit of burning. Even if you have not committed a sin which leads to death, 1 John 5:16-17 you nevertheless have sinned, you have become filthy. Thus, the Lord will wash away the filth of the sons and daughters of Zion, and he will cleanse the blood from their midst, then a spirit of judgment as a recompense for the filth, a spirit of burning for the blood. And most of us, whenever we sin more grievously, need not lye or the washing with soap, but the spirit of burning. 3. On this account, Jesus—now perhaps I discover the reason—baptizes in the Holy Spirit and in fire, Luke 3:16 not the same man in the Holy Spirit and in fire, but the holy man in the Holy Spirit, while another man, after he has believed, after he has been deemed worthy of the Holy Spirit, after he has sinned again, Jesus washes in fire, so that it is not the same man who is baptized by Jesus in the Holy Spirit and in fire. (2) Blessed, then, is the one who is baptized in the Holy Spirit and does not need the baptism by fire, but three times unhappy is that man who has need to be baptized in fire, though Jesus takes care of both of them. For a shoot from the stump of Jesse will come forth, and a branch will grow out of the root, Isaiah 11:1 a shoot for those who are punished, a branch for the righteous. So God is a consuming fire Heb. 12:29 and God is light, 1 John 1:5 a consuming fire to sinners, a light to the just and holy ones. (3) And blessed is he who shares in the first resurrection, Rev. 20:6 he who has kept the baptism of the Holy Spirit. Who is he who is saved in another resurrection? He who needs the baptism from fire, when he comes before that fire and the fire tests him, and when that fire finds wood, hay and stubble to burn. 1 Cor. 3:12-13 (4) Now because of this, since these things are said, since we have brought together as far as we can the words of Scripture, let us put away these things into the heart and let us try to live in light of them, to see if we can become pure before our final departure and, after we prepare our works for the final departure, after we depart, be accepted among those who are good and be saved in Christ Jesus, to whom is the glory and the power for the ages of ages. Amen. – Origen, Homilies on Jeremiah 2.2.3-4, 3.1-4

(2) The next sentence is likely to produce a challenge for us. For either we understand it as what follows the preceding, in which case we will rethink carefully concerning the recompense for sins; or it seems that it does not follow concerning what is fished and hunted; and so it puts us into a challenge which is not met. For he says, “And I will recompense first their wrongs and their sins doubly, for which they have profaned my land with the carcasses of their abominations and with their lawlessness, with which they filled my inheritance.” Jeremiah 16:18 Whether some scribes, by not understanding, removed the first, or whether the Seventy who supervised, removed it, God would know. Nevertheless, by comparing the remaining translations, we discover a reliable text: And first I will recompense their wrongs doubly, in order that it might be clear that even though there may be those worthy of blessedness due to their second works, since they are men and are born in sins, it is necessary first that they receive what is due for their sins. And observe if the word is not true. Who will not receive their due for sins if not he who, after believing and receiving forgiveness for sins—so that he hears Jesus saying, Your sins are forgiven, sin no longer —sins no longer? Luke 5:20, John 5:14, 8:11 But if after forgiveness of sins and the divine agency of the washing of the regeneration Titus 3:5 we should sin—as we are the masses who are not as mature as the Apostles—and after sinning, we should also do something as we ought along with the sinning, what awaits us, one must ponder. (3) What if we finish our life with sins but also with what is commendable, will we be saved through what is commendable and acquitted concerning those sins which were knowingly committed? Or will we be punished for the sins but receive no recompense for what is commendable? But neither the one way—where I say one does receive his due for what is base but does not receive his due for what is better—is in accord with God being just; nor is the other view—where I say that he receives his due for what is better but does not receive his due for what is base—in accord with God being just, who wants to purify and cut down evil. For suppose that you have built, after the foundation which Christ Jesus has taught, not only gold, silver, and precious stones—if indeed you possess gold and much silver or little—suppose that you have silver, precious stone, but I say not only these elements, but suppose that you have also wood and hay and stubble, 1 Cor. 3:11-13 what does he wish you to become after your final departure? To enter afterwards then into the holy lands with your wood and with your hay and stubble so that you may defile the Kingdom of God? But again do you want to be left behind in the fire on account of the hay, the wood, the stubble, and to receive nothing due you for the gold and the silver and precious stone? This is not reasonable. What then? 6. It follows that you receive the fire first due to the wood, which consumes the wood and the hay and the stubble. For to those able to perceive, our God is said to be in reality a consuming fire. And the Prophet was silent about what consuming is when he said, Our God is a consuming fire, Deut. 4:24, Heb. 12:29 but has left it for us to determine. Because he said, God is a consuming fire, there is something which is consumed. What then is the thing which is consumed? For he does not consume what is according to the image and likeness, he does not consume his own creation but the accumulated hay, the accumulated wood, the accumulated stubble. … (3) All of us thus who have matter for that fire will receive first for our sins. 7. But someone among those who hear will ask to discuss also the word “doubly.” Jer. 16:18 For suppose that I receive first what is due for sins in order that, when I receive what is due for sins, after this what is said by the Apostle may be fulfilled: If anyone’s work will be burned up, he will suffer loss, though he will be saved, but only as through fire. 1 Cor. 3:15 Why do I at some time receive doubly what is due for sins? But one must say that a servant who knew the will of the master and did not act according to his will will be thrashed not a few times but many times. Luke 12:47 Therefore, it is worthwhile that those who sin from the pagan nations receive one time what is due for their sins, but we receive doubly what is due for our faults. “For if we sin deliberately after receiving the knowledge of the truth, there no longer remains a sacrifice for sins, but a fearful prospect of judgment, and a fury of fire which will consume the adversaries.” Heb. 12:26-27 – Origen, Homilies on Jeremiah 16.5.2-3, 6.1, 7.1

If Celsus, indeed, had understood our teaching regarding the Spirit of God, and had known that “as many as are led by the Spirit of God, these are the sons of God,” Romans 8:14 he would not have returned to himself the answer which he represents as coming from us, that “God put His own Spirit into a body, and sent it down to us;” for God is perpetually bestowing of His own Spirit to those who are capable of receiving it, although it is not by way of division and separation that He dwells in (the hearts of) the deserving. Nor is the Spirit, in our opinion, a body, any more than fire is a body, which God is said to be in the passage, “Our God is a consuming fire.” Hebrews 12:29 For all these are figurative expressions, employed to denote the nature of intelligent beings by means of familiar and corporeal terms. In the same way, too, if sins are called “wood, and straw, and stubble,” we shall not maintain that sins are corporeal; and if blessings are termed “gold, and silver, and precious stones,” 1 Corinthians 3:12 we shall not maintain that blessings are corporeal; so also, if God be said to be a fire that consumes wood, and straw, and stubble, and all substance of sin, we shall not understand Him to be a body, so neither do we understand Him to be a body if He should be called “fire.” – Origen, Against Celsus, Book 6, chapter 70

But as it is in mockery that Celsus says we speak of “God coming down like a torturer bearing fire,” and thus compels us unseasonably to investigate words of deeper meaning, we shall make a few remarks, sufficient to enable our hearers to form an idea of the defense which disposes of the ridicule of Celsus against us, and then we shall turn to what follows. The divine word says that “our God is a consuming fire,” Heb. 12:29, Deut. 4:24 and that “He draws rivers of fire before Him;” Daniel 7:9-10 nay, that He even enters in as “a refiner’s fire, and as a fuller’s herb,” to purify His own people. But when He is said to be a “consuming fire,” we inquire what are the things which are appropriate to be consumed by God. And we assert that they are wickedness, and the works which result from it, and which, being figuratively called “wood, hay, stubble,” 1 Cor. 3:12 God consumes as a fire. The wicked man, accordingly, is said to build up on the previously-laid foundation of reason, “wood, and hay, and stubble.” If, then, any one can show that these words were differently understood by the writer, and can prove that the wicked man literally builds up wood, or hay, or stubble, it is evident that the fire must be understood to be material, and an object of sense. But if, on the contrary, the works of the wicked man are spoken of figuratively under the names of wood, or hay, or stubble, why does it not at once occur (to inquire) in what sense the word fire is to be taken, so that wood of such a kind should be consumed? For (the Scripture) says: “The fire will try each man’s work of what sort it is. If any man’s work abide which he has built thereupon, he shall receive a reward. If any man’s work be burned, he shall suffer loss.” 1 Cor. 3:13-15 But what work can be spoken of in these words as being burned, save all that results from wickedness? Therefore our God is a consuming fire in the sense in which we have taken the word; and thus He enters in as a “refiner’s fire,” to refine the rational nature, which has been filled with the lead of wickedness, and to free it from the other impure materials, which adulterate the natural gold or silver, so to speak, of the soul. And, in like manner, “rivers of fire” are said to be before God, who will thoroughly cleanse away the evil which is intermingled throughout the whole soul. But these remarks are sufficient in answer to the assertion, that thus they were made to give expression to the erroneous opinion that God will come down bearing fire like a torturer.  – Origen, Against Celsus, Book 4, chapter 13

Now after this the Lord goes on to say: “But your sons will be inhabitants of the desert for forty years.” Num. 14:33 And he clarifies the mystery that that number contains when he says: “In accordance with the number of days,” he says, “during which you surveyed the land, forty days, a day for a year, you will receive for your sins for forty years.” Num. 14:34 I fear to discuss the secrets of this mystery; for I see that the reckoning of sins and punishments is comprehended here. For if as a punishment for the sin of one day a year is prescribed to each sinner, and if an equal number of years will have to be completed in the penalties, in accordance with the reckoning of days in which the sin is committed, I fear that perhaps for those of us who sin daily and who perhaps do not spend a day of our life without sin, that perhaps the very ages, or even the ages of ages may not be able to suffice for the punishments that will have to be paid. For in the fact that that people are tormented in the desert for forty years for a transgression of forty days, and they are not permitted to enter the holy land, a certain likeness of the future judgment seems to be shown, when the reckoning of sins needs to be made up. Yet it might be possible that there will be a sort of compensation for good works, or even a compensation for “the evils that each one has received in this life,” as Abraham showed concerning Lazarus. Luke 16:25 But to have complete knowledge of these things belongs to no one except to him to whom “the Father has committed all judgment.” John 5:22 Now the idea of a day of sin being reckoned as a year of punishment is shown not only in this book, in which there is absolutely nothing that can be doubted, but similar things are also indicated in the little book “The Shepherd,” if indeed that writing seems deserving to be received by anyone. (The Shepherd 3.6.4, quoted earlier) – Origen, Homilies on Numbers 8.1.5

…Pass now from the example of the body to the wounds of the soul. As often as the soul sins, just so often it is wounded. And lest you be in doubt that it is wounded by sins, as if by arrows and swords, listen to the apostle when he admonishes us to take up “the shield of faith by which,” he says, “you can extinguish all the flaming arrows of the evil one.” Eph. 6:16 So you see that sins are the “arrows of the evil one,” which are aimed at the soul. But not only does the soul suffer the wounds of arrows, but it also experiences fractures of its feet, when “snares are prepared for its feet,” Psa. 57:6 and when its “steps are made to trip.” Psa. 37:31 Well, how long do you think it will take for these wounds and others like them to be cured? Indeed, if we could only see how with each sin our inner man is wounded, how bad words inflict a wound! Have you not read the words: “swords inflict wounds, but not as much as the tongue”? Sir. 28:18 The soul is wounded, then, even by the tongue. It is also wounded by evil thoughts and desires, but it is fractured and shattered by the works of sin. If we could see all this and feel the scars of a soul that has been wounded, we would certainly resist sin unto death. 1 John 5:16-17 But now, just as those who are filled with a demon or the mentally insane do not perceive it when they are wounded, because they lack natural senses, so is it with us. Since we have become crazed by the desires of the world, or intoxicated with vices, we cannot feel the extent of the wounds or the extent of the grief we are bringing on our soul by sinning. And therefore it is perfectly consistent that the reckoning of the punishment, that is, of the medical treatment and cure, be extended over time, and that for each wound the length of healing be prolonged as well, according to the nature of the wound. So then, the justice and kindness of God will also become evident in those very penalties of the soul. Let the one who hears this who has committed sin come to his senses and sin no more. John 8:11 For conversion in the present life and a penance that is carried out fruitfully will bring swift medicine to wounds of this sort. For penance not only heals a past wound, but it does not allow the soul to be wounded further by sin. Or rather, I should add this: If, for instance, I am a sinner, will the same punishment be mine if I have sinned once in a matter in which I also sin a second and third time and even more frequently? It will not be like that, but rather, the measure of the punishment must also be determined by the manner, number and measure of the sin. For God will give to us “the bread of tears” and he will offer drink to us “in tears,” but this will be “according to measure.”Psa. 80:5 – Origen, Homilies on Numbers 8.1.7-8

Cyprian:

It is one thing to stand for pardon, another thing to attain to glory: it is one thing, when cast into prison, not to go out thence until one has paid the uttermost farthing; Matthew 5:26 another thing at once to receive the wages of faith and courage. It is one thing, tortured by long suffering for sins, to be cleansed and long purged by fire; another to have purged all sins by suffering. It is one thing, in fine, to be in suspense till the sentence of God at the day of judgment; another to be at once crowned by the Lord. – Cyprian, Epistle 51.20

Lactantius:

The same divine fire, therefore, with one and the same force and power, will both burn the wicked and will form them again, and will replace as much as it shall consume of their bodies, and will supply itself with eternal nourishment: which the poets transferred to the vulture of Tityus. Thus, without any wasting of bodies, which regain their substance, it will only burn and affect them with a sense of pain. But when He shall have judged the righteous, He will also try them with fire. Then they whose sins shall exceed either in weight or in number, shall be scorched by the fire and burnt: but they whom full justice and maturity of virtue has imbued will not perceive that fire; for they have something of God in themselves which repels and rejects the violence of the flame. So great is the force of innocence, that the flame shrinks from it without doing harm; which has received from God this power, that it burns the wicked, and is under the command of the righteous. – Lactantius, The Divine Institutes, Book 7, chapter 21

Apostolic Constitutions:

“Let us pray for our brethren that are at rest in Christ, that God, the lover of mankind, who has received his soul, may forgive him every sin, voluntary and involuntary, and may be merciful and gracious to him, and give him his lot in the land of the pious that are sent into the bosom of Abraham, and Isaac, and Jacob, with all those that have pleased Him and done His will from the beginning of the world, whence all sorrow, grief, and lamentation are banished.” – Apostolic Constitutions, 8:4, 41

Theodore of Heraclea:

1 Corinthians 3:14–15 – The finest of teachings is not undone by this present life; rather, it remains, and appears even more glorious in deeds at that time. Therefore, the one who teaches these things—which are able to remain even then, when the Lord, the Master, has appeared more greatly—will certainly receive the reward for them. But the one who teaches the opposite, he says, may for a time prevail in the present life, yet will be utterly destroyed at the time of the end. He not only loses the reward for his labors here—what he could have gained by choosing to labor for the finest things—but even if he is saved on account of some other reason capable of saving him, he does not escape the testing by fire, which he must undergo because of the worst teachings. For this is what the phrase means: “but so as through fire.” The continuation of the thought intends this: “he will be burned, but as through fire.” That is, because he said, “he himself will be saved,” this means that the disobedience of those taught does not condemn the teacher. For even if he does not receive a reward and is condemned, still he will be saved—unless the fire seizes him as he passes through, on account of his own offenses. Thus, he will be saved—not as entirely escaping judgment, but as one who will be tested through fire concerning his own works. — Theodore of Heraclea, Fragments on 1 Corinthians (340 AD) [Theodore of Heraclea, Fragmenta in epistulam i ad Corinthios]

Hilary of Poitiers:

For since no living person is pure in His sight, how can His judgment be something desirable? When we must give an account for every idle word (Matthew 12:36), shall we desire the Day of Judgment? On that day, we must endure the tireless fire and the grievous punishments necessary to expiate sins. Even the soul of the Blessed Mary was pierced by a sword so that the thoughts of many hearts might be revealed (Luke 2:35). If this virgin, made capable of conceiving God, will encounter the severity of this judgment, who will dare to escape?” Hilary of Poitiers, Tractatus in Ps 118; PL 9:523 (364 AD)

Gregory of Nyssa:

For the perfection of bodies that rise from that sowing of death is, as the Apostle tells us, to consist in incorruption and glory and honour and power; but any diminution in such excellences does not denote a corresponding bodily mutilation of him who has risen again, but a withdrawal and estrangement from each one of those things which are conceived of as belonging to the good. Seeing, then, that one or the other of these two diametrically opposed ideas, I mean good and evil, must any way attach to us, it is clear that to say a man is not included in the good is a necessary demonstration that he is included in the evil. But then, in connection with evil, we find no honour, no glory, no incorruption, no power; and so we are forced to dismiss all doubt that a man who has nothing to do with these last-mentioned things must be connected with their opposites, that is. with weakness, with dishonour, with corruption, with everything of that nature, such as we spoke of in the previous parts of the discussion, when we said how many were the passions, sprung from evil, which are so hard for the soul to get rid of, when they have infused themselves into the very substance of its entire nature and become one with it. When such, then, have been purged from it and utterly removed by the healing processes worked out by the Fire, then every one of the things which make up our conception of the good will come to take their place; incorruption, that is, and life, and honour, and grace, and glory, and everything else that we conjecture is to be seen in God, and in His Image, man as he was made. – Gregory of Nyssa, On the Soul and the Resurrection (c. 382)

Just as those who refine gold from the dross which it contains not only get this base alloy to melt in the fire, but are obliged to melt the pure gold along with the alloy, and then while this last is being consumed the gold remains, so, while evil is being consumed in the purgatorial fire, the soul that is welded to this evil must inevitably be in the fire too, until the spurious material alloy is consumed and annihilated by this fire…If, then whether by forethought here, or by purgation hereafter, our soul becomes free from any emotional connection with the brute creation, there will be nothing to impede its contemplation of the Beautiful; for this last is essentially capable of attracting in a certain way every being that looks towards it. If, then, the soul is purified of every vice, it will most certainly be in the sphere of Beauty. The Deity is in very substance Beautiful; and to the Deity the soul will in its state of purity have affinity, and will embrace It as like itself. – Gregory of Nyssa, On the Soul and the Resurrection (c. 382)

“When he has quitted his body and the difference between virtue and vice is known he cannot approach God till the purging fire shall have cleansed the stains with which his soul was infested. That same fire in others will cancel the corruption of matter, and the propensity to evil.” – Gregory of Nyssa, Sermon on the Dead (PG 13:445, 448)

• Different translation: “If a man distinguishes in himself what is peculiarly human from what is irrational, and if he be on the watch for a life of greater urbanity for himself, in this present life he will purify himself of any evil contracted, and overcome the irrational by reason. If he has inclined to the irrational pressure of the passions…he may afterward, in a very different manner, be very much interested in what is better, when, after his departure out of the body, he gains knowledge of the difference between virtue and vice and finds that he is not able to partake of divinity until he has been purged of the filthy contagion in his soul by the purifying fire.” – Gregory of Nyssa, Sermon on the Dead

Cyril of Jerusalem:

“Then we make mention also of those who have already fallen asleep: first, the patriarchs, prophets, apostles, and martyrs, that through their prayers and supplications God would receive our petition; next, we make mention also of the holy fathers and bishops who have already fallen asleep, and, to put it simply, of all among us who have already fallen asleep, for we believe that it will be of very great benefit to the souls of those for whom the petition is carried up, while this holy and most solemn sacrifice is laid out” – Cyril of Jerusalem, Catechetical Lectures 23:5:9 (350 AD)

Gregory of Nazianzus:

“Let these men then if they will, follow our way, which is Christ’s way; but if they will not, let them go their own. Perhaps in it they will be baptized with Fire, in that last Baptism which is more painful and longer, which devours wood like grass, 1 Corinthians 3:12-19 and consumes the stubble of every evil.” – Gregory of Nazianzus, Oration 39

Ephrem the Syrian:

According to the grace of God which has been given to me, as a wise builder I laid the foundation—that is, the builder of the Spirit. And the foundation itself is faith; besides that which I preached to you, there is no other. If anyone builds on this with good works like gold, or with corrupt teaching and shameful works like stubble, the proving fire of the great day will test that work. Whoever’s building remains will receive the reward of his building in the Kingdom. But whoever’s building burns will suffer loss—that is, he will be tormented. For although the resurrection will raise him up and give him life, yet he will live miserably, as through fire. — Ephrem the Syrian, Commentary on 1 Corinthians. (Ephrem the Syrian’s Commentary on the Pauline Epistles, translated by the Mekhitarist Fathers)

“Lay me not with sweet spices: for this honour avails me not; Nor yet incense and perfumes: for the honour benefits me not. Burn sweet spices in the Holy Place: and me, even me, conduct to the grave with prayer. Give ye incense to God: and over me send up hymns. Instead of perfumes of spices: in prayer make remembrance of me.” – Ephraim the Syrian, His Testament (ante A.D. 373), NPNF2, in XIII:135

Basil the Great:

“Neither shall any widow receive mercy” (cf. Isaiah 9:17). For what is weak and helpless is worthy of mercy; but what is strong in wickedness and evil is fit for rejection and hatred. —Then he adds that His wrath has not yet turned away, but still His hand is stretched out, because of those leading astray among the people and those being led astray, among whom all are lawless, evil, and speaking unrighteous things. —Yet the threat contains a certain suggestion of benefit, that “Lawlessness shall be burned up like fire” (cf. Isaiah 9:18). For the material prepared from lawlessness is destined for destruction for the benefit of mankind, as arranged by the good Master. And, he says, “like dry grass it shall be consumed by fire, and it shall be burned up in the thickets of the forest” (cf. Isaiah 9:18). So long as the soul is buried in earthly passions, its passions, like grass, spring from the mind of the flesh, passing through one another, with a generation that reproduces itself—each arising from the previous. For just as grass is most prolific among plants and its growth never ends, but always the end of one generation becomes the beginning of the next, so is the nature of sins: it hands itself on. Fornication begets fornication; the habit of lying becomes the mother of more lies, and he who practices theft grows bold easily in wrongdoing. For a preceding sin becomes the occasion for further sin. —If, then, we expose our sin through confession, we have made it dry grass, worthy to be consumed by the purifying fire. This, however, is burned in the thickets of the forest. Consider what has been said concerning forests in the First Book of Kings: the people, under attack, entered the forest and refrained from eating (1 Samuel 14:24-26). Likewise, Absalom, being attacked, entered the forest (2 Samuel 18:6-9). If our sin does not become like dry grass, it will not be consumed by fire, nor will it be completely burned up. —And the thickets of the forest signify those who are enslaved and mentally overshadowed, those who in the hidden place of their heart retain many evils. Then he adds, “Because through the anger of the Lord’s wrath the whole land has been burned” (cf. Isaiah 9:19). He shows that earthly things are delivered over to the punishing fire for the benefit of the soul, just as the Lord also indicates, saying: “I came to cast fire upon the earth, and would that it were already kindled!” (Luke 12:49). —“And the people shall be as a man burned by fire” (cf. Isaiah 9:19). He does not threaten annihilation, but indicates purification, according to what is said by the Apostle: “If anyone’s work is burned up, he will suffer loss, but he himself will be saved, yet so as through fire” (1 Corinthians 3:15). – Basil the Great, Commentary on Isaiah, chapter IX 

Epiphanius:

“Useful too is the prayer fashioned on their behalf…it is useful,because in this world we often stumble either voluntarily or involuntarily.” – Epiphanius, Panarion, 75:8 (375 A.D.)

Ambrosiaster:

“…Yet he himself will be saved, but only as through fire.” 1 Corinthians 3:15 … And he said: “but only as through fire,” so that this salvation is not without punishment, because he did not say: “He will be saved through fire,” as if by his merit he would be unharmed by fire and saved, having been tested by fire; but when he says: “but only as through fire,” he shows that he will indeed be saved, but will suffer the pains of fire; so that, being purged by fire, he may become saved, and not, like the faithless, be tormented forever in eternal fire: so that in some way it is of some value to have believed in Christ. For he must always blush who sees that he defended falsehood instead of truth: and in a similar way, he will always have confidence in God who, having rejected falsehood, followed the truth; and having scorned impiety, submitted to piety. For whatever is outside the Catholic [faith], is contrary [to it]. — Ambrosiaster, Commentary on 1 Corinthians (380 AD)

Didymus the Blind ?

“Indeed, the sword Genesis 3:24 signifies the loving-kindness of God toward all, since it is a symbol of chastening power that guards…Of those who are called toward virtue, there are many causes. And even the sword is usefully placed for this very reason. Scripture contains not only the promises of Paradise but also the threats against those unwilling to follow God’s commands, and the myriad corrections that call the soul toward virtue. These corrections—though severe—serve to prepare one for entrance into Paradise and to hinder the bitterness of punishment. For the sword in Scripture is often spoken of in the place of punishment: “By the sword all sinners of the people shall perish.” Yet not all die by the sword; rather, the name of the sword signifies the future punishment to be brought upon sinners. The guard, therefore, in which the sword and the cherubim have been placed, Genesis 3:24 as was said before, exists for benefit, so that, if there should arise in someone a desire for the entrance, guidance might occur through them: the cherubim symbolizing the knowledge of the truth, which the one wishing to enter must partake of, and the sword the painful punishment— for through many afflictions one must enter the kingdom, as it is written. Acts 14:22 That the punishment laid down by God is turning and not necessarily coming to pass is taught by the events concerning the Ninevites, who by repentance turned away wrath; and to them the threats were reversed. – Didymus the Blind, Commentary on Genesis 3:24 

[This quote can be taken as Purgatory or not]

Ambrose of Milan:

Therefore we need purification, because we have touched the dead (cf. Numbers 19:11). The Law commands us to be cleansed: who is so great as to be above the Law? Even the Nazarite, the holy one of God, if he has touched a dead body, is declared unclean (cf. Numbers 6:6–9). Therefore he shaves his head and lays aside his hair as something no longer holy; and again he prays that he may be heard, who before, because of contact with the dead, could not pray: he counts his days as irrational, because he had drawn near to what is irrational. Therefore he lays aside what is dead and superfluous of his head, that he may be reconciled to Christ. Therefore, if the Nazarite is purified, we too must be purified. 13. We have all touched the dead. For who will boast that he has kept his heart pure, or who will dare to say that he is free from sins? Perhaps there is someone who has not sinned in word—though such a one is rare—of whom God says, as of holy Job: He did not sin with his lips (Job 2:10); yet he could not always have had pure thoughts of his heart, for the devil casts himself into the heart of man. Suppose someone has always kept his heart guarded with constant and vigilant watchfulness; yet, living among sinners, he too must needs be purified. Hence Isaiah, when he said: Woe is me! for I am undone; because I am a man of unclean lips, and I dwell in the midst of a people of unclean lips (Isaiah 6:5); immediately one of the Seraphim descended and touched his lips with a coal, to cleanse his unclean lips. 14. There is not one baptism only: there is the one which the Church administers here, through water and the Holy Spirit, by which it is necessary for catechumens to be baptized. There is also another baptism, of which the Lord Jesus says: I have a baptism to be baptized with; and how am I straitened till it be accomplished! (Luke 12:50). And surely He had already been baptized in the Jordan, as the preceding passages show (cf. Matthew 3:13–17); but this is the baptism of His passion, by which each one is also cleansed by His own blood. There is also a baptism at the gate of Paradise, which before did not exist: but after the sinner was cast out, there began to be the fiery sword, which God placed there (Genesis 3:24), which did not exist before, when there was no sin. Sin began, and baptism began: that by it those who wish to return to Paradise may be cleansed, so that when they have returned they may say: We went through fire and through water (Psalm 66:12). Here through water, there through fire. Through water, that sins may be washed away; through fire, that they may be burned up. But what is more grievous is that we endure fire both here and there. 15. Who is it that baptizes in this fire? Not a presbyter, not a bishop, not John, who says: I baptize you with water for repentance (Matthew 3:11); not an Angel, not an Archangel, not Dominions, not Powers: but He of whom John says: He who comes after me is mightier than I, whose sandals I am not worthy to carry; He will baptize you with the Holy Spirit and with fire. His winnowing fan is in His hand, and He will thoroughly cleanse His threshing floor and gather His wheat into the granary; but the chaff He will burn with unquenchable fire (Matthew 3:11–12). It is not of this baptism, which is performed by the priests of the Church, that the Lord Himself testifies. For after the consummation of the age, when the angels are sent to separate the good and the wicked, this baptism will take place: when through the furnace of fire iniquity shall be burned away, so that in the kingdom of God the righteous may shine like the sun in the kingdom of their Father (cf. Matthew 13:41–43). And if anyone be as holy as Peter, as John, he is baptized with this fire. Then the great Baptist—so I call him, as Gabriel named him, saying: He shall be great (Luke 1:15)—will come, he will see many standing before the gate of Paradise, he will move the revolving sword, he will say to those on the right, who have no grievous sins: Enter, you who have confidence, you who do not fear the fire. For I foretold to you: Behold, I come like fire (cf. Isaiah 66:15); and through Ezekiel I said: Behold, I will go forth against Jerusalem, and I will blow upon you in the fire of My wrath, that you may melt as lead and iron melt (cf. Ezekiel 22:19–22). 16. Let then the consuming fire come, let it burn away in us the lead of iniquity, the iron of sin, and make us pure gold. Let it burn my loins and my heart, that I may think good thoughts and desire those things which belong to chastity. But because one purified here still has need to be purified there, may He also purify us there, when the Lord shall say: Enter into my rest (cf. Psalm 95:11; Hebrews 4:3); so that each of us, scorched by that flaming sword but not consumed, having entered into that pleasantness of Paradise, may give thanks to his Lord, saying: You brought us into refreshment (cf. Psalm 66:12). He therefore who has passed through the fire enters into rest. He passes from things material and worldly to those incorruptible and everlasting. 17. This is a different fire by which unwilled but accidental sins are burned away, which the Lord Jesus has prepared for His servants, to cleanse them from this dwelling which is mixed with the dead. That other fire is the one appointed for the devil and his angels, of which He says: Depart into the everlasting fire (Matthew 25:41); in which that rich man was burning, who begged that a drop of water might be dripped onto him from Lazarus’s finger (Luke 16:24). But Lazarus, reclining in Abraham’s bosom (Luke 16:22–23), was enjoying eternal life, which the Prophet promises to himself, saying: I shall live and keep Your words (Psalm 118[119]:17). I shall live, he says, as though not yet living; for here we live in shadow. – Ambrose of Milan, Exposition on Psalm 118, Sermon 3, sections 12-17, PL 15:1226-1228, (384 AD) 

All must be tested by fire, whoever desires to return to Paradise; for it is not written without purpose that when Adam and Eve were cast out from the dwelling of Paradise, God placed at the entrance of Paradise the flaming sword which turns every way (Genesis 3:24). All must pass through the flames, whether it be that John the Evangelist, whom the Lord loved so much that He said to Peter concerning him: If I will that he remain… what is that to you? You follow me (John 21:22). Some have doubted about his death, but we cannot doubt about his passing through the fire; for he is in Paradise and is not separated from Christ. Or whether it be Peter, who received the keys of the kingdom of heaven, who walked upon the sea—it is necessary that he say: We went through fire and through water, and you brought us into refreshment (Psalm 66:12). But for John, the fiery sword shall quickly turn aside; for no iniquity is found in him whom righteousness has loved. If there was any human fault in him, divine love has purified it; His wings are as the wings of fire (cf. Psalm 104:4; Hebrews 1:7). Whoever has within him here the fire of charity will not fear there the fire of the sword. To Peter himself, who so often offered his life for Christ, it shall be said: Pass through, recline (cf. Luke 12:37). But he will say: He tested us in fire, as silver is tested by fire (cf. Psalm 66:10); for in him whom much water could not quench love, how will fire drive him away? But he will be tested like silver; I shall be tested like lead: until the lead melts, I shall burn. If no silver is found in me, alas for me! I shall be thrust down to the lowest hell, or be utterly consumed like stubble. But if any gold or silver is found in me, not by my deeds but by the mercy and grace of Christ, through the ministry of the priesthood, perhaps I too shall say: Indeed, they who hope in You shall not be confounded (Psalm 24:3). Therefore by that fiery sword iniquity shall be burned away, which sits upon the leaden talent (cf. Zechariah 5:7–8). For this reason, He alone could not feel that fire—Christ, who is the righteousness of God—because He committed no sin; for the fire found in Him nothing that it could burn away. Indeed, for Him alone were the everlasting doors lifted up, that the King of Glory might enter in, not one guilty of any charge (cf. Psalm 24:7–10). And here indeed His flesh tasted death; for otherwise He could not have risen again. What I have read, I affirm; what I have not read, I reverently leave to those who know: confessing this one thing, that whatever that flesh endured, it endured for this reason—that it might mark out the path for others, either of triumph through the passion of martyrdom or of passage into Paradise by following His footsteps. Let no one therefore presume for himself, let no one boast of merits, let no one boast of power: but let us all hope through the Lord Jesus to find mercy; for we shall all stand before His judgment seat (cf. Romans 14:10). From Him I shall seek pardon, from Him forgiveness; for what other hope is there for sinners? And he who thinks himself gold here still has lead; and he who thinks himself a grain of wheat has chaff that can be burned. Yet here many appear to themselves as gold. I do not envy them; but still the gold shall be tested, it shall be burned so that it may be proved. For thus it is written: I will try them as gold is tried in the furnace (Zechariah 13:9). Therefore let them take heed, for all shall be tested. Many therefore who think themselves gold should also follow humility, that they may burn away their vices. But here vain boasting prevails; therefore to many who think themselves masses of gold, the one wiser than the mass of gold says: The furnace shall test us all. Therefore, since we must be tested, let us so act that we may deserve to be proved by the divine judgment. Let us hold fast to humility while we are here, so that when each of us comes to the judgment of God, to those fires through which we shall pass, he may say: See my humility and deliver me (cf. Psalm 24:18); for if he be proud, arrogant, stubborn, he will not be able to say this. No one will say: “See my pride”; but rather, See my humility, that by its merit he may deserve to be delivered from that fire. – Ambrose of Milan, Exposition on Psalm 118, Sermon 20, sections 12-15,  PL 15:1487-1488, (384 AD)

Give, Oh Lord, rest to Thy servant Theodosius, that rest Thou hast prepared for Thy saints….I love him, therefore will I follow him to the land of the living; I will not leave him till by my prayers and lamentations he shall be admitted unto the holy mount of the Lord, to which his deserts call him.” – Ambrose, De obitu Theodosii, PL 16:1397 (395 A.D.)

Chromatius of Aquileia:

Then follows: “Be reconciled with your adversary quickly, while you are with him on the way, lest perhaps the adversary deliver you to the judge, and the judge deliver you to the officer, and you be cast into prison. Amen I say to you, you will not come out from there until you have paid the last farthing” (Matthew 5:25–26). Some interpret this saying of the Lord as meaning that such an adversary, whether by one’s own fault or another’s, who has become an enemy, should quickly be restored to peace and friendship while we are with him on the way—that is, during the course of this present life—lest, when we depart from this world, each one, as a forgetter of charity and guilty of enmities, begin to be handed over to God the Judge, and be delivered by the Judge to the officer—that is, the overseer of punishments—and, being cast into the prison of Gehenna, pay the due penalties of sin. But this interpretation does not seem to hold complete reason. – Chromatius of Aquileia, Treatise on the Gospel of St. Matthew, Treatise 8, chapter 1 (PL 20:347B-C)

• This interpretation that Chromatius says some held to, is a similar interpretation of Matthew 5:25-26 that Tertullian uses, and he calls it the true interpretation of the scripture (quoted earlier, On the Soul ch. 35). Chromatius ultimately rejected this interpretation, but it shows that this was still held to by Christians even in the 400s, which shows that post-mortem punishment.

John Chrysostom:

“But since Paul’s saying appears to some to tell the other way, come let us bring it forward also and search it out thoroughly. For having said, “If any man’s work abide which he has built thereon, he shall receive a reward; and if any man’s work shall be burned, he shall suffer loss,” he adds, “but himself shall be saved, yet so as through fire.” What shall we say then to this? Let us consider first what is “the Foundation,” and what “the gold,” and what “the precious stones,” and what “the hay,” and what the “stubble.” “The Foundation,” then, he has himself plainly signified to be Christ, saying, “For other foundation can no man lay than that which is laid, which,” he says “is Jesus Christ.” Next, the building seems to me to be actions. Although some maintain that this also is spoken concerning teachers and disciples and concerning corrupt heresies: but the reasoning does not admit it. For if this be it, in what sense, while the “work is destroyed,” is the “builder” to be saved, though it be “through fire?” Of right, the author ought rather of the two to perish; but now it will be found that the severer penalty is assigned to him who has been built into the work. For if the teacher was the cause of the wickedness, he is worthy to suffer severer punishment: how then shall he be “saved?” If, on the contrary, he was not the cause but the disciples became such through their own perverseness, he is no whit deserving of punishment, no, nor yet of sustaining loss: he, I say, who built so well. In what sense then does he say, “he shall suffer loss?” From this it is plain that the discourse is about actions… – Homily 9 on First Corinthians

“If any man build upon this foundation, gold, silver, costly stones, wood, hay, stubble.” 1 Corinthians 3:12 For after the faith there is need of edification: and therefore he says elsewhere, “Edify one another with these words.” 1 Thessalonians 5:11; 4:5 For both the artificer and the learner contribute to the edifying. Wherefore he says, “But let every man take heed how he builds thereon.” 1 Corinthians 3:10 But if faith had been the subject of these sayings, the thing affirmed is not reasonable. For in the faith all ought to be equal, since “there is but one faith;” Ephesians 4:5 but in goodness of life it is not possible that all should be the same. Because the faith is not in one case less, in another more excellent, but the same in all those who truly believe. But in life there is room for some to be more diligent, others more slothful; some stricter, and others more ordinary; that some should have done well in greater things, others in less; that the errors of some should have been more grievous, of others less notable. On this account he says, “Gold, silver, costly stones, wood, hay, stubble — every man’s work shall be made manifest:” — his conduct; that is what he speaks of here:— “If any man’s work abide which he built thereupon, he shall receive a reward; if any man’s work shall be burned, he shall suffer loss.” Whereas, if the saying related to disciples and teachers, he ought not to “suffer loss” for disciples refusing to hear. And therefore he says, “Every man shall receive his own reward according to his own labor” not according to the result, but according to “the labor.” For what if the hearers gave no heed? Wherefore this passage also proves that the saying is about actions. Now his meaning is this: If any man have an ill life with a right faith, his faith shall not shelter him from punishment, his work being burnt up. The phrase, “shall be burned up,” means, “shall not endure the violence of the fire.” But just as if a man having golden armor on were to pass through a river of fire, he comes from crossing it all the brighter; but if he were to pass through it with hay, so far from profiting, he destroys himself besides; so also is the case in regard of men’s works. For he does not say this as if he were discoursing of material things being burnt up, but with a view of making their fear more intense, and of showing how naked of all defense he is who abides in wickedness. Wherefore he said, “He shall suffer loss:” lo, here is one punishment: “but he himself shall be saved, but so as by fire;” lo, again, here is a second. And his meaning is, He himself shall not perish in the same way as his works, passing into nought, but he shall abide in the fire. He calls it, however, “Salvation,” you will say; why, that is the cause of his adding, “so as by fire:” since we also used to say, “It is preserved in the fire,” when we speak of those substances which do not immediately burn up and become ashes. For do not at sound of the word fire imagine that those who are burning pass into annihilation. And though he call such punishment “Salvation,” be not astonished. For his custom is in things which have an ill sound to use fair expressions, and in good things the contrary. For example, the word “Captivity” seems to be the name of an evil thing, but Paul has applied it in a good sense, when he says, “Bringing into captivity every thought to the obedience of Christ.” 2 Corinthians 10:5 And again, to an evil thing he has applied a good word, saying, Sin reigned, Romans 5:21 here surely the term reigning is rather of auspicious sound. And so here in saying, “he shall be saved,” he has but darkly hinted at the intensity of the penalty: as if he had said, “But himself shall remain forever in punishment.” – Homily 9 on First Corinthians

…. And together with these reasons collect also examples, some in the present life, some in the Holy Scriptures. Consider that Abraham slew his own son, and neither shed a tear nor uttered a bitter word. But he, you say, was Abraham. Nay, thou surely hast been called to a nobler field of action. And Job grieved indeed, but so much as was proper for a father who loved his children and was very solicitious for the departed; whereas what we now do, is surely the part of haters and enemies. For if when a man was taken up to court and crowned, thou were smiting yourself and lamenting, I should not say that you were a friend of him who was crowned, but a great enemy and adversary. Nay, say you, not even as it is do I mourn for him, but for myself. Well, but this is not the part of an affectionate person, to wish for your own sake that he were still in the conflict and subject to the uncertainty of the future, when he might be crowned and come to anchor; or that he should be tossed in mid ocean, when he might have been in port. 8. But I know not where he has gone, you say. Why do you not know, tell me? For according as he lived well or otherwise, it is evident where he will go. Nay, on this very account I lament, you say, because he departed being a sinner. This is a mere pretext and excuse. For if this were the reason of your mourning for the departed, you ought to have formed and corrected him, when he was alive. The fact is thou dost every where look to what concerns yourself, not him. But grant that he departed with sin upon him, even on this account one ought to rejoice, that he was stopped short in his sins and added not to his iniquity; and help him as far as possible, not by tears, but by prayers and supplications and alms and offerings. For not unmeaningly have these things been devised, nor do we in vain make mention of the departed in the course of the divine mysteries, and approach God in their behalf, beseeching the Lamb Who is before us, Who takes away the sin of the world — not in vain, but that some refreshment may thereby ensue to them. Not in vain does he that stands by the altar cry out when the tremendous mysteries are celebrated, “For all that have fallen asleep in Christ, and for those who perform commemorations in their behalf.” For if there were no commemorations for them, these things would not have been spoken: since our service is not a mere stage show, God forbid! Yea, it is by the ordinance of the Spirit that these things are done. Let us then give them aid and perform commemoration for them. For if the children of Job were purged by the sacrifice of their father, why do you doubt that when we too offer for the departed, some consolation arises to them? Since God is wont to grant the petitions of those who ask for others. And this Paul signified saying, that in a manifold Person your gift towards us bestowed by many may be acknowledged with thanksgiving on your behalf. 2 Corinthians 1:11 Let us not then be weary in giving aid to the departed, both by offering on their behalf and obtaining prayers for them: for the common Expiation of the world is even before us. Therefore with boldness do we then intreat for the whole world, and name their names with those of martyrs, of confessors, of priests. For in truth one body are we all, though some members are more glorious than others; and it is possible from every source to gather pardon for them, from our prayers, from our gifts in their behalf, from those whose names are named with theirs. Why therefore do you grieve? Why mourn, when it is in your power to gather so much pardon for the departed? – John Chrysostom, Homily 41 on 1 Corinthians

Mourn for those who have died in wealth, and did not from their wealth think of any solace for their soul, who had power to wash away their sins and would not. Let us all weep for these in private and in public, but with propriety, with gravity, not so as to make exhibitions of ourselves; let us weep for these, not one day, or two, but all our life. Such tears spring not from senseless passion, but from true affection. The other sort are of senseless passion. For this cause they are quickly quenched, whereas if they spring from the fear of God, they always abide with us. Let us weep for these; let us assist them according to our power; let us think of some assistance for them, small though it be, yet still let us assist them. How and in what way? By praying and entreating others to make prayers for them, by continually giving to the poor on their behalf. This deed has some consolation; for hear the words of God Himself, when He says, I will defend this city for My own sake, and for My servant David’s sake. 2 Kings 20:6 If the remembrance only of a just man had so great power when deeds are done for one, how great power will it not have? Not in vain did the Apostles order that remembrance should be made of the dead in the awesome Mysteries. They know that great gain results to them, great benefit; for when the whole people stands with uplifted hands, a priestly assembly, and that awful Sacrifice lies displayed, how shall we not prevail with God by our entreaties for them? And this we do for those who have departed in faith, while the catechumens are not thought worthy even of this consolation, but are deprived of all means of help save one. And what is this? We may give to the poor on their behalf. This deed in a certain way refreshes them. For God wills that we should be mutually assisted; else why has He ordered us to pray for peace and the good estate of the world? Why on behalf of all men? Since in this number are included robbers, violaters of tombs, thieves, men laden with untold crimes; and yet we pray on behalf of all; perchance they may turn. As then we pray for those living, who differ not from the dead, so too we may pray for them. Job offered sacrifice for his children, and freed them from their sins. It may be, said he, that they have renounced God in their hearts. Job 1:5 Thus does one provide for one’s children! He said not, as many do nowadays, I will leave them property; he said not, I will procure them honor; he said not, I will purchase an office; he said not, I will buy them land; but, it may be that they have renounced God in their hearts. For what profit is there in those things? None at all, in those that remain here. I will make the King of all things favorable to them, and then they will no more want anything. The Lord, says one, is my Shepherd, I shall not want. Psalm 23:4 This is great wealth, this is treasure. If we have the fear of God, we want nothing; if we have not this, though we have royalty itself, we are the poorest of all men. Nothing is like the man that fears the Lord. For the fear of the Lord, it is said, surpasses all things. Sirach 25:11 This let us procure; let us do all things for its sake. If need be that we lay down our lives, if our body must be mangled, let us not spare them; let us do all, to obtain this fear. For thus shall we abound above all men; and shall obtain those good things to come in Christ Jesus our Lord, to whom, etc. – John Chrysostom, Homily 3 on Philippians

Jerome:

“These things the Lord God showed to me. And behold, the Lord God was calling for judgment unto fire. And it devoured the great deep and ate up a part at the same time. And I said: O Lord God, be silent, I beg. Who will raise up Jacob, for he is a little one? The Lord had pity concerning this. But also this will not be, said the Lord God.” Amos 7:4-6 First the Lord shows the prophet the maker of the locusts who are being born at the beginning of the late rain, and after the late rain he shows the mower king, or the king’s barber, and to express word for word, the mowing of King Sennacherib by which he shaved and laid waste all the ten tribes Amos 7:1 Now the Lord shows the same thing to Nebuchadnezzar; or rather, he calls him and orders him to come against Judah and Jerusalem. But he calls him to set the temple and Jerusalem on fire and to execute judgment by fire concerning those who were once his people. When fire had come for judgment to fulfill the command of the Lord, it devoured the great deep and consumed at the same time a part, all the cities of Judah, and the part of the Lord that was called his temple. When the prophet had seen this, he did not say to the Lord, as above, “Be merciful, I beg,” Amos 7:2 but Be silent, or “cease.” He says this to entreat by his pleas the one whom he had now seen starting to speak to cease, especially since there is no one else who is able to raise up Jacob who is lying, a little one, and humiliated. Only the Lord can do this, he who is able to lead back to the land of “Judah those who were captured and carried away to Chaldea. For to be sure once and for all we have applied the ten tribes, which were called Israel, to the person of the heretics, and to the two tribes, over which Judah had control, to the church and to the sinners of the church, based on the prophet Hosea and the psalmist, who says: “The sons of Ephraim, who bend and shoot with the bow, have returned on the day of battle.” Psalm 78:9 The sinners of the church confess the right faith, to be sure, but because of the filth of their vices they require purifying flames. Therefore the Lord now shows that he is calling for fire as judgment so that the fire may test the quality of each one’s work 1 Cor. 3:15 and that which is written may be fulfilled: “Walk in the light of your fire and in the flame which you have kindled.” Isaiah 50:11 On this basis it is also said to Babylon: “You have coals of fire; you will sit on them. These will be a help to you.” Isaiah 47:14 Also in the psalm, a deceitful tongue and one filled with lies is said to require purification by the fire of coals: “What will be given to you, or what will be added to you for a deceitful tongue? The sharp arrows of the mighty, with coals that lay waste.” Psalm 120:3-4 From these coals of the altar the coal of the two Testaments is taken with tongs, and it cleanses the unclean lips of Isaiah so that he is able to prophesy the word of the Lord. Isaiah 6:6-7 But fire is summoned for judgment, and it devours first the deep, that is, all kinds of sinners, wood, hay, straw, 1 Cor. 3:12 and afterward consumes all at once a part, that is, it comes to the holy ones of the Lord, who are regarded as his possession and his portion. For it is time for judgment to begin from the house of the Lord. 1 Peter 4:17 And in Ezekiel it is commanded to those who would undergo punishments: “Begin from my holy ones.” Ezekiel 9:6 And we read in the apostle: “If someone’s work burns, he will suffer loss. He himself will be saved, but nevertheless in such a way as if through fire.” 1 Cor. 3:15 Since all of us are in sin, and we are subject to the truth of judgment, the Lord will have compassion on us, and because we are little ones, he will raise us at the time of the resurrection, or he will raise us, who were lying in the vices, through the virtues. This is what the Lord promises and says: But also this will not be. And quite appropriately he said but also this because he had already said above “This will not be.” Amos 7:3 For “he will not be angry to the end, nor will he threaten forever. He has not dealt with us according to our sins, nor paid us back according to our iniquities. As far as the east is from the west, so far has he removed our iniquities from us. As a father has compassion on his children, so has the Lord compassion on them who fear him.” Psalm 103:9–13 – Jerome, Commentary on Amos 7:4-6

He himself is coming like a refining fire, like a fuller’s herb. Mal. 3:2 For “a fire shall burn in his sight, and around him a mighty tempest.” Ps 50:3. Then he will call heaven above and earth to adjudicate his people; they will draw streams of fire before him, all the sinners rolling on. Now the Lord is called a fire, and a consuming fire, Heb 12:29 that burns our wood, hay and straw. 1 Cor 3:12. And not only a fire, but also a fuller’s herb, which is expressed in Hebrew as borit, and the Septuagint translates πόαν, that is, the “fuller’s herb.” To those who sin gravely, he is a refining and consuming fire; but [to those] who commit light sins, he is a fuller’s herb, which restores the cleanness to things that have been washed, in accordance with what is written in Isaiah: “The Lord shall wash away the filth of the sons and daughters of Zion, and shall wash away the blood from the midst of them, by the spirit of judgment and by the spirit of burning.” Isa. 4:4. Those who have filth require the spirit of judgment in order to be washed; those who are full of blood need the spirit of burning to remove the outer layer of blood that is smeared on them. He will sit refining and cleansing as silver, so that, according to Ezekiel, whatever in our gold or silver, that is, in our understanding and eloquent speech, has been mixed together with bronze, tin, iron and lead may be boiled away in the furnace of the Lord, so that pure gold and silver remains. Ezek 22:20-22. Whence the Lord says in the Gospel: “I have come to cast fire on the earth, and how I wish that it be kindled.” Lk. 12:49 And he will purify the sons of Levi. “For it is time for judgment to begin with the house of God.” 1 Pet. 4:17 And elsewhere it is written: “Begin by my holy ones.” Ezek. 9:6 Now in the sons of Levi, understand the entire office of priesthood. But if the priests have to be made clean and washed that pure gold and silver may remain, what must be said about the rest? When they are purified and washed, then they shall offer to the Lord just sacrifices, and he will be pleased with their sacrifice, which they offer for Judah and Jerusalem, that is, for those who confess the Lord and see his peace with their mind, like the days of old, and like the ancient years, so that just as they pleased God in the beginning, so after sin and repentance they may begin to please, when all have been cleansed from the filth of sins. – Jerome, Commentary on Malachi 3:1-6

“According to the grace of God given to me, as a wise architect I laid the foundation, and another builds upon it. For no one can lay another foundation besides that which has been laid, which is Christ Jesus. But if anyone builds upon this foundation with gold, silver, precious stones, wood, hay, straw, each one’s work will be made manifest. For the Day of the Lord will disclose it, because it will be revealed in fire, and the fire will test what sort of work each has done. If anyone’s work which he built upon it remains, he will receive a reward. If anyone’s work is burned up, he will suffer loss. Yet he himself will be saved, but only as through fire.” 1 Corinthians 3:10-15 If someone’s work has burned and perished, and he has sustained the loss of his labor, he will indeed lose the reward of his labor [or: work], but he himself will be saved, yet not without the testing of fire. Therefore, if someone’s work remains which he has built upon it, he will be saved without the testing of fire, and there will certainly be some difference between one salvation and another. – Jerome, Adversus Jovinianum, Book 2, chapter 22 (PL 23:317B-D)

[Jerome interprets 1 Cor 3:15 as proof that not all the saved avoid purgation and he insists that Paul’s words show a distinction: some are saved without the fire’s probation, others only by undergoing it.]

“Other husbands scatter on the graves of their wives violets, roses, lilies, and purple flowers; and assuage the grief of their hearts by fulfilling this tender duty. Our dear Pammachius also waters the holy ashes and the revered bones of Paulina, but it is with the balm of almsgiving.” – Jerome, To Pammachius, Epistle 66:5 (397 A.D.), in NPNF2, VI:136

Augustine:

[Psalm 37:2.] He therefore recounts and entrusts to God the distress he was enduring, fearing, it seems, something more grievous than the place in which he presently was. For he openly declares that he is in distress, and there is no need for interpretation, suspicion, or conjecture; from his words it is clear in what evil he finds himself, and there is no need for us to inquire, but only to understand what he says. And unless he feared something worse than that in which he was already held, he would not have begun in this way: “O Lord, rebuke me not in Your indignation, nor chasten me in Your wrath” (Psalm 6:1). For it will happen that some will be corrected in the wrath of God, and rebuked in His indignation. And perhaps not all who are rebuked will be corrected; yet some will be saved in correction. That this shall happen is certain, since correction is named; yet it is as though by fire. But there will also be some who are rebuked and not corrected. For surely He will rebuke those to whom He will say, “I was hungry and you gave Me no food; I was thirsty and you gave Me no drink” (Matthew 25:42), and the rest that follows there, where He reproves a certain inhumanity and barrenness in the wicked set on His left hand, to whom it is said, “Depart from Me into the eternal fire prepared for the devil and his angels” (Matthew 25:41). Fearing these more grievous things, beyond this present life—in whose evils he laments and groans—he prays and says: “O Lord, rebuke me not in Your indignation.”  Let me not be among those to whom You will say: “Depart into the eternal fire prepared for the devil and his angels” (Matthew 25:41). “Nor chasten me in Your wrath” (Psalm 6:1): but purge me in this life, and make me such that I may no longer need the purgatorial fire, because of those who will be saved, yet so as through fire. Why? Unless because they build upon the foundation wood, hay, stubble? Yet they ought to build gold, silver, precious stones, and be secure from both kinds of fire—not only from that eternal fire which shall eternally torment the wicked, but also from that which shall amend those who shall be saved through fire. For it is said: “He himself shall be saved, yet so as through fire” (1 Corinthians 3:15). And because it is said, “he shall be saved,” that fire is disregarded. Yet clearly, although they are saved through fire, that fire will be more grievous than anything a person can suffer in this life. And you know how much the wicked have suffered here, and what they may suffer; yet they have suffered no more than what the good have also been able to endure. For what punishment has any evildoer, thief, adulterer, criminal, or blasphemer suffered under the law, which the martyr has not also borne in confessing Christ? Therefore, the evils of this life are much lighter; and yet see how people will do whatever you command in order to avoid them. How much better, then, to do what God commands, that they may not suffer those more grievous punishments? – Augustine, Explanations of the Psalms 37:3 (AD 392) PL 36:397

“If the baptized person fufils the obligations demanded of a Christian, he does well. If he does not-provided he keeps the faith ,without which he would perish forever-no matter in what sin or impurity remains, he will be saved, as it were, by fire; as one who has built on the foundation, which is Christ, not Gold, silver, and precious stones, but wood, hay straw,that is, not just and chasted works but wicked and unchaste works.” – Augustine, Faith and Works, 1:1 (413 A.D.)

(§67)It is believed, moreover, by some, that men who do not abandon the name of Christ, and who have been baptized in the Church by His baptism, and who have never been cut off from the Church by any schism or heresy, though they should live in the grossest sin and never either wash it away in penitence nor redeem it by almsgiving, but persevere in it persistently to the last day of their lives, shall be saved by fire; that is, that although they shall suffer a punishment by fire, lasting for a time proportionate to the magnitude of their crimes and misdeeds, they shall not be punished with everlasting fire. But those who believe this, and yet are Catholics, seem to me to be led astray by a kind of benevolent feeling natural to humanity…– Augustine, The Enchiridion, 67

(§68) But as these most plain and unmistakable declarations of the apostles cannot be false, that obscure saying about those who build upon the foundation, Christ, not gold, silver, and precious stones, but wood, hay, and stubble (for it is these who, it is said, shall be saved, yet so as by fire, the merit of the foundation saving them ), must be so interpreted as not to conflict with the plain statements quoted above. Now wood, hay, and stubble may, without incongruity, be understood to signify such an attachment to worldly things, however lawful these may be in themselves, that they cannot be lost without grief of mind. And though this grief burns, yet if Christ hold the place of foundation in the heart—that is, if nothing be preferred to Him, and if the man, though burning with grief, is yet more willing to lose the things he loves so much than to lose Christ—he is saved by fire. If, however, in time of temptation, he prefer to hold by temporal and earthly things rather than by Christ, he has not Christ as his foundation; for he puts earthly things in the first place, and in a building nothing comes before the foundation. Again, the fire of which the apostle speaks in this place must be such a fire as both men are made to pass through, that is, both the man who builds upon the foundation, gold, silver, precious stones, and the man who builds wood, hay, stubble. For he immediately adds: “The fire shall try every man’s work, of what sort it is. If any man’s work abide which he has built thereupon, he shall receive a reward. If any man’s work shall be burned, he shall suffer loss; but he himself shall be saved, yet so as by fire” (1 Cor. 3:13-15). The fire then shall prove, not the work of one of them only, but of both. Now the trial of adversity is a kind of fire which is plainly spoken of in another place: “The furnace proves the potter’s vessels: and the furnace of adversity just men” (Sir. 27:5). And this fire does in the course of this life act exactly in the way the apostle says. If it come into contact with two believers, one caring for the things that belong to the Lord, how he may please the Lord, that is, building upon Christ the foundation, gold, silver, precious stones; the other “caring for the things that are of the world, how he may please his wife” (1 Cor. 7:33), that is, building upon the same foundation wood, hay, stubble—the work of the former is not burned, because he has not given his love to things whose loss can cause him grief; but the work of the latter is burned, because things that are enjoyed with desire cannot be lost without pain. But since, by our supposition, even the latter prefers to lose these things rather than to lose Christ, and since he does not desert Christ out of fear of losing them, though he is grieved when he does lose them, he is saved, but it is so as by fire; because the grief for what he loved and has lost burns him. But it does not subvert nor consume him; for he is protected by his immoveable and incorruptible foundation. – Augustine, The Enchiridion, 68

(§69) And it is not impossible that something of the same kind may take place even after this life. It is a matter that may be inquired into, and either ascertained or left doubtful, whether some believers shall pass through a kind of purgatorial fire, and in proportion as they have loved with more or less devotion the goods that perish, be less or more quickly delivered from it. This cannot, however, be the case of any of those of whom it is said, that they shall not inherit the kingdom of God, unless after suitable repentance their sins be forgiven them. When I say suitable, I mean that they are not to be unfruitful in almsgiving; for Holy Scripture lays so much stress on this virtue, that our Lord tells us beforehand, that He will ascribe no merit to those on His right hand but that they abound in it, and no defect to those on His left hand but their want of it, when He shall say to the former, “Come, you blessed of my Father, inherit the kingdom” (Matt. 25:34), and to the latter, “Depart from me, you cursed, into everlasting fire” (Matt. 25:41). – Augustine, The Enchiridion, 69

(§110) Nor can it be denied that the souls of the dead are benefited by the piety of their living friends, who offer the sacrifice of the Mediator, or give alms in the church on their behalf. But these services are of advantage only to those who during their lives have earned such merit, that services of this kind can help them. For there is a manner of life which is neither so good as not to require these services after death, nor so bad that such services are of no avail after death; there is, on the other hand, a kind of life so good as not to require them; and again, one so bad that when life is over they render no help. Therefore, it is in this life that all the merit or demerit is acquired, which can either relieve or aggravate a man’s sufferings after this life. No one, then, need hope that after he is dead he shall obtain merit with God which he has neglected to secure here. And accordingly it is plain that the services which the church celebrates for the dead are in no way opposed to the apostle’s words: “For we must all appear before the judgment seat of Christ, that every one may receive the things done in his body, according to that he has done, whether it be good or bad”; for the merit which renders such services as I speak of profitable to a man, is earned while he lives in the body. It is not to everyone that these services are profitable. And why are they not profitable to all, except because of the different kinds of lives that men lead in the body? When, then, sacrifices either of the altar or of alms are offered on behalf of all the baptized dead, they are thank-offerings for the very good, they are propitiatory offerings for the not very bad, and in the case of the very bad, even though they do not assist the dead, they are a species of consolation to the living. And where they are profitable, their benefit consists either in obtaining a full remission of sins, or at least in making the condemnation more tolerable. – Augustine, The Enchiridion, 110

For our part, we recognize that even in this life some punishments are purgatorial — not, indeed, to those whose life is none the better, but rather the worse for them, but to those who are constrained by them to amend their life. All other punishments, whether temporal or eternal, inflicted as they are on every one by divine providence, are sent either on account of past sins, or of sins presently allowed in the life, or to exercise and reveal a man’s graces. They may be inflicted by the instrumentality of bad men and angels as well as of the good. For even if any one suffers some hurt through another’s wickedness or mistake, the man indeed sins whose ignorance or injustice does the harm; but God, who by His just though hidden judgment permits it to be done, sins not. But temporary punishments are suffered by some in this life only, by others after death, by others both now and then; but all of them before that last and strictest judgment. But of those who suffer temporary punishments after death, all are not doomed to those everlasting pains which are to follow that judgment; for to some, as we have already said, what is not remitted in this world is remitted in the next, Matthew 12:31-32 that is, they are not punished with the eternal punishment of the world to come. – Augustine, City of God, Book 21, chapter 13 (420 AD)

…Yet if either of these ages has received the sacraments of the Mediator, then, although the present life be immediately brought to an end, the child, having been translated from the power of darkness to the kingdom of Christ, shall not only be saved from eternal punishments, but shall not even suffer purgatorial torments after death. For spiritual regeneration of itself suffices to prevent any evil consequences resulting after death from the connection with death which carnal generation forms. – Augustine, City of God, Book 21, chapter 16 (420 AD)

It is then, I say, the same reason which prevents the Church at any time from praying for the wicked angels, which prevents her from praying hereafter for those men who are to be punished in eternal fire; and this also is the reason why, though she prays even for the wicked so long as they live, she yet does not even in this world pray for the unbelieving and godless who are dead. For some of the dead, indeed, the prayer of the Church or of pious individuals is heard; but it is for those who, having been regenerated in Christ, did not spend their life so wickedly that they can be judged unworthy of such compassion, nor so well that they can be considered to have no need of it. As also, after the resurrection, there will be some of the dead to whom, after they have endured the pains proper to the spirits of the dead, mercy shall be accorded, and acquittal from the punishment of the eternal fire. For were there not some whose sins, though not remitted in this life, shall be remitted in that which is to come, it could not be truly said, “They shall not be forgiven, neither in this world, neither in that which is to come.” Matthew 12:32 – Augustine, City of God, Book 21, chapter 24 (420 AD)

…In the books of the Maccabees we read of sacrifice offered for the dead. Howbeit even if it were nowhere at all read in the Old Scriptures, not small is the authority, which in this usage is clear, of the whole Church, namely, that in the prayers of the priest which are offered to the Lord God at His altar, the Commendation of the dead has also its place… – Augustine, On the Care of the Dead chapter 3

“But by the prayers of the holy Church, and by the salvific sacrifice, and by the alms which are given for their spirits, there is no doubt that the dead are aided, that the Lord might deal more mercifully with them than their sins would deserve. The whole Church observes this practice which was handed down by the Fathers: that it prays for those who have died in the communion of the Body and Blood of Christ, when they are commemorated in their own place in the sacrifice itself; and the sacrifice is offered also in memory of them, on their behalf. If, then, works of mercy are celebrated for the sake of those who are being remembered, who would hesitate to recommend them, on whose behalf prayers to God are not offered in vain? It is not at all to be doubted that such prayers are of profit to the dead; but for such of them as lived before their death in a way that makes it possible for these things to be useful to them after death” – Augustine, Sermon 172:2

“That there should be some fire even after this life is not incredible, and it can be inquired into and either be discovered or left hidden whether some of the faithful may be saved, some more slowly and some more quickly in the greater or lesser degree in which they loved the good things that perish, through a certain purgatorial fire” – Augustine, Handbook on Faith, Hope, and Charity 18:69 [421 A.D.]

“The time which interposes between the death of a man and the final resurrection holds souls in hidden retreats, accordingly as each is deserving of rest or of hardship, in view of what it merited when it was living in the flesh. Nor can it be denied that the souls of the dead find relief through the piety of their friends and relatives who are still alive, when the Sacrifice of the Mediator [Mass] is offered for them, or when alms are given in the Church. But these things are of profit to those who, when they were alive, merited that they might afterward be able to be helped by these things. There is a certain manner of living, neither so good that there is no need of these helps after death, nor yet so wicked that these helps are of no avail after death” – Augustine, Handbook on Faith, Hope, and Love PL 29:109).

Again, the fire of which the apostle speaks in this place must be such a fire as both men are made to pass through, that is, both the man who builds upon the foundation gold, silver, precious stones, and the man who builds wood, hay, stubble. For he immediately adds: “The fire shall try every man’s work, of what sort it is. If any man’s work abide which he has built thereupon, he shall receive a reward. If any man’s work shall be burned, he shall suffer loss; but he himself shall be saved, yet so as by fire” (1 Corinthians 3:13–15). The fire then shall prove, not the work of one of them only, but of both. Now the trial of adversity is a kind of fire which is plainly spoken of in another place: “The furnace proves the potter’s vessels: and the furnace of adversity just men” (Sirach 27:5). And it is not impossible that something of the same kind may take place even after this life… some believers shall pass through a kind of purgatorial fire, and in proportion as they have loved with more or less devotion the goods that perish, be less or more quickly delivered from it. – Augustine, Handbook on Faith, Hope, and Love, Chapter 69

“There is an ecclesiastical discipline, as the faithful know, when the names of the martyrs are read aloud in that place at the altar of God, where prayer is not offered for them. Prayer, however, is offered for other dead who are remembered. It is wrong to pray for a martyr.” — Augustine, Sermons 159:1 [411 A.D.]

Why is it wrong to pray for a martyr? Because his sins are already forgiven and he will not be going through any purging/cleansing fire. You only pray for Christians who you believe need them, who may be going through a cleansing before entering paradise. So when we read the church fathers telling us to pray for the dead and that God may forgive their sins, its because they all believed your prayer can actually benefit them. 

Remigius:

The “unquenchable fire” is the punishment of eternal damnation; either because it never totally destroys or consumes those it has once seized on, but torments them eternally; or to distinguish it from purgatorial fire which is kindled for a time and again extinguished. — Remigius (Thomas Aquinas, Catena Aurea on Matthew 3)

Caesarius of Arles:

In the Gospel text which was read to us a little while ago, dearest brethren, we heard the Apostle say: “Other foundation no one can lay, but that which has been laid, which is Christ Jesus. But if anyone builds upon this foundation, gold, silver, precious stones, wood, hay, straw—the work of each will be made manifest, for the day of the Lord will declare it, since the day is to be revealed in fire. The fire will assay the quality of everyone’s work: if his work abides which he has built thereon, he will receive reward; if his work burns he will lose his reward, but himself will be saved, yet so as through fire.” 1 Corinthians 3:11-15 There are many people who understand this text incorrectly, deceiving themselves with a false assurance. They believe that if they build serious sins upon the foundation of Christ, those very offenses can be purified by transitory flames and they themselves can later reach eternal life. This kind of understanding must be corrected, dearest brethren, because men deceive themselves when they flatter themselves in this way. For in that passing fire, of which the Apostle said: “He himself will be saved, yet so as through fire,” not serious but slight sins are purged. What is worse, not only greater sins, but even small ones, if they are very many, ruin a man. For this reason, even though not all sins are to be mentioned, at least some of them should be, whether more or less serious, lest anyone foolishly try to excuse himself by saying that he does not know which are lesser sins and which are serious offenses…[Lists lesser sins and serious offenses] … (3)…There is no doubt that these actions and similar ones belong to the slight offenses which, as I already said, can scarcely be counted. From these sins, not only all the Christian people, but even all the saints sometimes cannot be free, and they never will be. Although we do not believe that the soul is killed by these sins, still they make it ugly by filling it with some kind of blisters and, as it were, a horrible scab. For this reason they allow the soul to come to the embraces of that heavenly spouse only with difficulty or with great confusion, for it is written concerning Him: “He prepared for Himself the Church not having spot or wrinkle.” Ephesians 5:27 (4) Therefore, they may continuously be redeemed by constant prayer, frequent fasting, more abundant almsgiving, and the forgiveness of those who sin against us. Otherwise, perhaps when they are collected and form a great heap, they may bury us. Whatever remains of these sins and is not redeemed by us will have to be purged in that fire of which the Apostle said: “It is to be revealed in fire, and if his work burns he will lose his reward.”⁵ As long as we live in this world, we ourselves exhaust ourselves in penance, or at least with the will and permission of God, we are afflicted with many tribulations because of those sins. If we are further grateful to God, we are set free. This happens as often as a husband or wife or child dies, or if our substance, which we love more than is necessary, is taken away—although we should love Christ more than that same possession, and if need be, should prefer to lose our substance rather than to deny Christ. Still, as I already said, because we love it more than we should, we cannot lose it either in life or in death without great sorrow. And still, if like good children, we give thanks to God who like a kind father permits it to be taken away, and admit with true humility that we suffer less than we deserve, in this way the sins themselves are purged in this world. Moreover, that fire of purgatory will find nothing in the future life, or at least very little, to burn away. But if we neither give thanks to God in tribulations nor redeem our own sins by good works, we will have to stay in that fire of purgatory as long as those above-mentioned slight sins are consumed like wood and hay and straw. – Caesarius of Arles, Sermon 179, chapters 1-4

(5) Perhaps someone may say: It makes no difference to me how long I will have to stay, as long as I pass on to eternal life. Let no one say this, dearest brethren, because that fire of purgatory will be more difficult than any punishment in this world can be seen or imagined or felt. Since it is written concerning the day of judgment: “One day will be as a thousand years, and a thousand years as one day,” 2 Peter 3:8 how does anyone know whether he is going to pass through that fire days or months or perhaps even years? Moreover, if a man is unwilling to put even one finger into the fire, why should he not fear that it might then be necessary to be tortured both in soul and body for a considerable time? For this reason, let each one labor with all his strength to avoid serious sins, and to redeem his slight offenses by good works in such a way that either very little or nothing of them may be seen to remain for that fire to consume. If those who commit serious sins refuse to correct them during life by the healing remedy of repentance, they will not be able to come to that fire of which the Apostle says: “But he himself will be saved, yet so as through fire.” 1 Corinthians 3:15 As was already said, they are going to hear instead that hard and irrevocable sentence: “Depart from me, accursed ones, into the everlasting fire.” Matthew 25:41 Therefore, those who desire to be freed from that eternal punishment and from the fire of purgatory should not commit serious sins. If they have already committed them, they should perform fruitful penance, not ceasing to redeem by good works also those small and even daily offenses. – Caesarius of Arles, Sermon 179, chapter 5

(8) Now in order that the things which we said above may be able to be fixed more firmly in your hearts, and the lesson of the Apostle may be understood more fully, I want to review them briefly for your charity. All the saints who faithfully serve God, striving to take time for reading and prayer and to persevere in good works, do not build serious sins or slight offenses, that is, wood, hay, and straw upon the foundation of Christ, but rather good works, that is, gold, silver, and precious stones. Such souls will pass without any violence through that fire of which the Apostle said: “It is to be revealed in fire.” 1 Corinthians 3:13 However, souls which are ready to commit slight offenses, even though they do not commit serious sins, if they are careless in redeeming them, they are not going to come to eternal life because of the fact that they believed in Christ and did not commit serious sins. Through the justice and mercy of God, as was already said, they must first be purified by the bitterest tribulations in this world, or through the goodness of God, they may free themselves by abundant almsgiving and kind forgiveness of enemies. Otherwise, they will have to be tortured for a long time by that fire of which the Apostle spoke, in order that they may reach eternal life without spot or wrinkle. Souls which have committed either murder or sacrilege or adultery or other sins like these, as was already said, if they have not been helped by worthy repentance, will not deserve to reach life by passing through the fire of purgatory, but they will be thrown to death in the eternal fire. – Caesarius of Arles, Sermon 179, chapter 8

The Lord further added: “Your children must wander in the desert for forty years.” Moreover, He explains the meaning of that mysterious number by saying: “Forty days you spent in scouting the land; forty years shall you suffer for your sins: one year for each day.” For my part I am afraid to examine the secrets of this mystery, for I see comprehended in it the calculation of sins and punishment. If each sinner is assigned punishment for the sin of one day, and according to the number of days he sins must spend so many years in punishment, I fear that perhaps for us who sin daily and spend no day of our life without offense, even ages and ages will not suffice to pay our penalties. In the fact that for forty days of sin those people were afflicted in the desert for forty years and not permitted to enter the holy land, a kind of similarity to the future judgment seems to be evident. At that time the number of sins will have to be calculated, unless perchance there is the balance of good works or of evils which a man has suffered in his life, as Abraham taught concerning Lazarus. However, it is within the power of no one to know these things perfectly, except Him to whom “The Father has given all judgment” (John 5:22). — Caesarius of Arles, Sermon 108, On the Twelve Scouts

• Caesarius is teaching what Origen taught about this passage in Numbers, and is almost word for word from what Origen taught in Homilies on Numbers 8.1.5 when discussing Purgatory.
• Origen: Now after this the Lord goes on to say: “But your sons will be inhabitants of the desert for forty years.” Num. 14:33 And he clarifies the mystery that that number contains when he says: “In accordance with the number of days,” he says, “during which you surveyed the land, forty days, a day for a year, you will receive for your sins for forty years.” Num. 14:34 I fear to discuss the secrets of this mystery; for I see that the reckoning of sins and punishments is comprehended here. For if as a punishment for the sin of one day a year is prescribed to each sinner, and if an equal number of years will have to be completed in the penalties, in accordance with the reckoning of days in which the sin is committed, I fear that perhaps for those of us who sin daily and who perhaps do not spend a day of our life without sin, that perhaps the very ages, or even the ages of ages may not be able to suffice for the punishments that will have to be paid. For in the fact that that people are tormented in the desert for forty years for a transgression of forty days, and they are not permitted to enter the holy land, a certain likeness of the future judgment seems to be shown, when the reckoning of sins needs to be made up. Yet it might be possible that there will be a sort of compensation for good works, or even a compensation for “the evils that each one has received in this life,” as Abraham showed concerning Lazarus. Luke 16:25 But to have complete knowledge of these things belongs to no one except to him to whom “the Father has committed all judgment.” John 5:22  —  Origen, Homilies on Numbers 8.1.5

However, to souls which have committed deeds worthy of temporal punishments this word of God is directed, that they may not depart from there, “Until they pay the last penny” (Matthew 5:26). They will pass through the stream of fire of which the prophetical word relates: “And a stream of fire flowed out before him” (Daniel 7:10), through the river of flame and a terrible lake of boiling masses. The delay in passing through here will be as great as was the material sin; the reasonable discipline of flames will punish a man as much as his guilt demands, and wise punishment will range as long as foolish iniquity committed sin. — Caesarius of Arles, Sermon 167

Gregory the Great:

In the Gospel the Lord says: “Walk while you have the light” (John 12:35). Through the Prophet also He says: “In an acceptable time I have heard you, and in the day of salvation I have helped you” (Isaiah 49:8). Which the Apostle Paul, explaining, says: “Behold, now is the acceptable time; behold, now is the day of salvation” (2 Corinthians 6:2). Solomon also says: Whatever your hand finds to do, do it with your might; for there is no work, nor reason, nor knowledge, nor wisdom in Sheol, where you are going (Ecclesiastes 9:10). David also says: “For His mercy endures forever” (Psalm 136:1). From these sayings it is clear that as each one departs hence, so shall he be presented in judgment. Yet concerning certain slight faults there is believed to be a purgatorial fire before the judgment, because Truth says that “whoever speaks a blasphemy against the Holy Spirit, it shall not be forgiven him, neither in this world nor in the world to come.” (Matthew 12:32). In this saying it is understood that certain faults can be forgiven in this world, and certain others in the world to come. For what is denied of one, the consequent understanding shows is granted concerning some. Yet, as I have said before, this is to be believed possible only for small and very slight sins, such as idle talk that is constant, immoderate laughter, or the fault of care for worldly matters, which is scarcely without fault even for those who know how they ought to avoid fault; or an error of ignorance in not grave matters, all of which still weigh upon one after death if they have not been loosed while one is yet living in this life. For when Paul says that Christ is the foundation, and adds: “If anyone builds upon this foundation gold, silver, precious stones, wood, hay, stubble; each one’s work shall be made manifest; for the day shall declare it, because it shall be revealed by fire; and the fire shall test what sort of work each one has done. If anyone’s work which he has built remains, he shall receive a reward; if anyone’s work shall be burned, he shall suffer loss; but he himself shall be saved, yet so as through fire.” (1 Corinthians 3:11–15). Although this can be understood of the fire of tribulation applied to us in this life, yet if anyone takes it of the fire of future purgation, it must be carefully considered that he said he can be saved through fire, not who builds upon this foundation iron, bronze, or lead—that is, greater sins, and therefore harder, and by then already unremovable—but wood, hay, stubble, that is, the smallest and lightest sins, which the fire easily consumes. Yet this must be known: that there at least, even for the least faults, no one shall obtain purgation unless by good deeds performed while still living in this life he has merited to obtain it there. – Gregory the Great, Dialogues, Book 4, chapter 39 (PL 77.393D-396D)

Oecumenius:

Are we then to understand it this way? Those who built with easily combustible material have been entirely cast out, for all their efforts have been lost. But he himself will be saved—who is this? The one who built with gold, silver, and precious stones. For having said of him that he will receive a reward, he now states what kind of reward: salvation. That is, he will be saved, yet with suffering, like someone passing through fire and having the small stain within him cleansed. For only God is completely without sin, but human beings—even the most righteous—are not entirely pure. It has been said that we all stumble in many ways, and that no one is free from sin, even if his life lasted only one day. And it has also been said by Malachi that God will wash and purify some like fire in a furnace and like a launderer’s soap. – Oecumenius, On 1 Corinthians 3.14-15 (catena)

Isidore of Seville:

Certain faults the Lord Himself does not deny will be forgiven in the future, when it is said: “But whoever shall have blasphemed against the Holy Spirit has no redemption, neither in this age nor in the age to come, but shall be guilty of an eternal offense.” Matthew 12:32 From this it is understood that there are certain sins which, though they are not forgiven in this age, yet in the future judgment can be destroyed by fire. If it were not so, the Lord would never have made this distinction. Of this fire John the Baptist, the forerunner of the Lord’s coming, speaks to the Jews: “There comes after me one whose sandals I am not worthy to carry; He shall baptize you in the Holy Spirit and fire.” Matthew 3:11 This means: He who will wash away or loosen your past sins by the Holy Spirit through the baptism of water, and some of those which follow afterward He will remit by the purgatorial fire. Of that fire, which is kindled not to cleanse the ungodly who are judged but to destroy the damned, the same John shortly after adds: “Whose winnowing fan is in His hand, and He will thoroughly cleanse His threshing floor and gather His wheat into the granary; but the chaff He will burn with unquenchable fire.” Matthew 3:12 For it is one thing to be baptized with fire, another to be burned with unquenchable fire. Of which same fire John also says: “Every tree that does not produce good fruit shall be cut down and cast into the fire.” Matthew 3:10 But of the fire of purgation the Lord Himself speaks in the Gospel: “Whoever shall say to his brother, ‘You fool,’ shall be guilty of Gehenna.” Matthew 5:22 He did not say of eternal fire; clearly because this offense is to be believed punished by purgatorial fire rather than by perpetual flame. Of this same distinction—of those whom the hurt of the future fire shall not touch, and of those who after the loss of fire shall receive salvation—the Apostle Paul explains, saying thus: “For no one can lay another foundation than that which is laid, which is Jesus Christ. But if anyone builds upon this foundation with gold, silver, precious stones; but another with wood, hay, stubble; if anyone’s work remains which he has built thereupon, he shall receive a reward; if anyone’s work shall be burned, he shall suffer loss, but he himself shall be saved, yet so as through fire.” 1 Corinthians 3:11-15 – Isidore of Seville, De ordine creaturarum, Chapter 14, section 6-9. (PL 83.948B-949A) – 615 AD, 

Bede:

Every sin shall be forgiven, except the blasphemy of the Spirit shall not be forgiven (cf. Matthew 12:31). He said that all sins can be forgiven through repentance, but that the blasphemy of the Spirit cannot be forgiven, because they were conscious of their own crime and, out of envy for the salvation brought by the work of the Holy Spirit, they said it was the work of the prince of demons. And whoever speaks a word against the Son of Man, it shall be forgiven him; but whoever speaks against the Holy Spirit, it shall not be forgiven him, neither in this world nor in the world to come (Matthew 12:32). He who, because of the visible weakness of the flesh, refuses to believe in my divinity can receive forgiveness through repentance; but he who, through despair, says that the Holy Spirit cannot forgive sins in baptism, or that the sacrament of the Lord’s Body and Blood received brings no benefit of forgiveness beyond other foods, shall obtain no forgiveness either here or in the world to come. And because He denies pardon to the despairing both here and in the future, without doubt He indicates the remission of certain sins in the future, such as idle words and superfluous thoughts, if one strives to do good and desires to amend evil deeds before the day of death. – Bede, Commentary on Matthew, Book 2, chapter 12 (PL 92.63) – 720 AD

[Luke 3:16] — “He will baptize you with the Holy Spirit and fire.” This is both the cleansing of sanctification and the testing of tribulation. However, the same Holy Spirit can also be understood as signified by the name of fire. Because He both enkindles through love and illuminates the hearts which He fills with wisdom. Hence, to those to whom it was said, “John indeed baptized with water, but you will be baptized with the Holy Spirit” (Acts XI), the same baptism of the spirit is perceived in the vision of fire. Some explain it in this way, that in the present we are baptized in the spirit, and in the future we will be baptized in fire. Namely, just as now we are reborn in the remission of all sins from water and the spirit, so also then, from certain light sins which have adhered to us as we go from here, we are cleansed by the baptism of purgatorial fire before the final judgment. As the Apostle says: “If anyone builds on this foundation, gold, silver, precious stones, wood, hay, straw, each one’s work will be made clear by fire. If anyone’s work remains which he has built on it, he will receive a reward. If anyone’s work is burned, he will suffer loss; but he himself will be saved, though as through fire” (I Corinthians III). Although this can also be understood of the fire of tribulation applied to us in this life, yet if anyone takes this as referring to the fire of future purification, it should be carefully considered, because he said that he can be saved through fire, not someone who builds on the foundation of Christ with iron, bronze, or lead, that is, greater and harder sins which are already unresolvable, but with wood, hay, and straw, that is, the smallest and lightest sins, which fire easily consumes. Nevertheless, it should be known that no one will obtain any purification even from the smallest sins there, unless he has acted with good deeds in this life so that he may deserve to obtain it there. — Bede, Commentary on Luke