Marriage 2.6.16

Whom, then, do you confess to be the creator of infants? The true God? But he did not make evil.

[Or the devil?] But he did not create human nature.

If union is evil, the condition of bodies is shameful too; so you also assign bodies to an evil creator.

God distinguished by sex what he would unite in action. Therefore bodily union comes from the one from whom bodies originate.

So many good things—bodies, sexes, unions—cannot have evil fruits. Nor are human beings made by God so that the devil may possess them under a lawful claim, as you say.