During some of the persecutions in the early centuries, the Roman rulers would order all the inhabitants of a region to sacrifice to the gods. Upon doing so, a person was given a certificate of sacrifice. Some Christians sought to avoid prison or martyrdom by obtaining a certificate through bribery or influence, even though they had not actually sacrificed to the gods.
You must not think, dearest brother, as some do, that those who receive certificates [of sacrifice] are to be put on a par with those who have sacrificed. . . . The one who has received the certificate may say, “I . . . had been made aware by the discourse of the bishop that we must not sacrifice to idols. . . . So I either went or directed some other person to go to the magistrate to say that I am a Christian and that I am not allowed to sacrifice. Because I cannot come to the devil’s altars, I shall pay a price for this purpose, that I may not do what is not lawful for me to do.” Now, he who has received a certificate is stained. . . . He has learned from our admonitions that he should not even have done this. Although his hand is pure and no contact of deadly food has polluted his lips, yet his conscience is polluted. Cyprian (c. 250, W), 5.330, 331.