To Florus 3.187

He persists in attacking us and adds: ‘As for those who have dared call this desire good against the evangelical and apostolic books, which they read to no purpose, you can see their saints sometimes sleeping with their daughters, sometimes carrying on with several concubines and wives. They do not see the apostle’s question: “What partnership is there between light and darkness, a believer and an unbeliever, Christ and Belial?” (2 Corinthians 6:14–15). They wander wrapped in desire’s cloud, enjoying its poison so much that, seized by madness, when they do this they think God has permitted it. As though they did not know the apostle said: “What they do in darkness is shameful even to mention”’ (Ephesians 5:12).

You surely see how he presses the matter of shame and thinks it tells powerfully against us, because we dare not call evil what we nevertheless acknowledge must be covered through modesty. Thus you have woven no garment to cover your doctrine’s deformity except the rags you accepted in your father and teacher’s inheritance.

He keeps rising up against us and turns directly to his opponent: ‘Come, defender of desire, describe its fruits and works in plain words. See, in opposing it I do not fear the light which it dreads and hates. “Everyone who does evil hates the light and does not come to the light, so that his deeds will not be exposed” (John 3:20). Do you see that desire is the source of evil, through which miserable souls serve lust unwillingly, because this is the only thing we do while the mind is unwilling?’

This is the source of your own statement: ‘Why is it that moving the lips, tongue, hands, and the bending of the back, neck, and sides for their proper tasks lies in our power, but when it comes to sowing children, the organs created for this task do not obey? Instead we wait for desire, as though acting under its own authority, to stir them; sometimes it fails to act when the mind is willing, although sometimes it acts when the mind is unwilling’ (Augustine, Marriage and Sexual Desire 1.7). You listed the functions of all the bodily members, emphasized their obedience to the will’s command, and said desire’s activity is the only thing we do against the mind’s will. What does Mani say? ‘Do you see that desire is the source of evil, through which miserable souls serve lust unwillingly, because this is the only thing we do while the mind is unwilling?’

But let us see what else he adds: ‘Every sin is outside the body, because it consists in action; but the fornicator sins against his own body (1 Corinthians 6:18). Every sin does not exist before it is committed, and afterward only the memory of the act remains, not its actual form. But desire’s evil, because it is natural, exists before it is enacted, increases while it is enacted, and afterward both appears and remains.’ Why, then, quarrel with us for calling you a Manichaean, when his writings contain nothing but what you say, and yours nothing but what he wants to persuade us to believe?

And that saying circulating on ordinary people’s lips, though put there by you, is contained in this same letter of Mani: If sin is not natural, why are infants baptized, when they plainly have done no evil themselves? I said it flies over many people’s tongues because it is a more popular argument, understood even by the slowest. In your books, however, you place your entire hope on it. Your teacher develops this very point as follows: ‘I must ask them in these words: If every evil consists in action, why does anyone receive purification by water before doing evil, when he has done no evil personally? Or if he has not yet acted but needs purification, it is possible to show that they are by nature shoots of evil stock—those very people whose madness prevents them from understanding either what they say or what they confidently affirm’ (compare 1 Timothy 1:7).

Do you hear how he insults us? He calls us mad and unable to understand what we say or affirm, because we deny that people are shoots of evil stock, although we baptize in purifying water even those who have done no evil—that is, infants. Many passages from his statements have now been quoted. Yet if the heading did not name his daughter Menoch and Mani, who calls himself Christ’s apostle, they would altogether announce you as their author (see this work 3.172). Since you say nothing except what you learned from Mani’s teaching, do you think catholics should regard you differently from the man through whom you drank in the mysteries of these doctrines?