On the Morals of the Manichaeans

³⁵ It is clear, then, I think, for what end we should abstain from flesh and wine. The end is threefold: to check indulgence, which is mostly practised in this sort of food, and in this kind of drink goes the length of intoxication; to protect weakness, on account of the things which are sacrificed and offered in libation; and, what is most praiseworthy of all, from love, not to offend the weakness of those more feeble than ourselves, who abstain from these things. You, again, consider a morsel of meat unclean; whereas the apostle says that all things are clean, but that it is evil to him that eats with offense.

And no doubt you are defiled by such food, simply because you think it unclean. For the apostle says, "I know, and am persuaded by the Lord Jesus, that there is nothing common of itself: but to him that esteems anything common, to him it is common." And every one can see that by common he means unclean and defiled. But it is folly to discuss passages of Scripture with you; for you both mislead people by promising to prove your doctrines, and those books which possess authority to demand our homage you affirm to be corrupted by spurious interpolations. Prove then to me your doctrine that flesh defiles the eater, when it is taken without offending any one, without any weak notions, and without any excess.