Marriage 2.13.26

But if you say, “They still had sexual capacity, but no offspring,” I will answer: the Creator gave the child whom the Creator promised. The child who is born is God’s work, not the work of intercourse. For he who made the first human being from dust (Genesis 2:7) forms everyone from seed. Just as the mud then taken as material was not the creator of the human being, so now that power of pleasure, producing and mixing the seed, does not itself complete the work. It offers God material from nature’s store, from which he is pleased to make a human being.