Eternal God, Made Man in Time

But perhaps you will say: “If I admit that the one who was born of a virgin at the end of time is the same person who was begotten of God the Father before all things, I will be implying that God was in the flesh before the beginning of the world, since I say that the one who was always God was afterward man. And so I will be saying that the man who was born later had always existed.” [a]

I do not want you to be confused by this blind ignorance and these murky misconceptions, so as to imagine that I am maintaining that the manhood born of Mary existed before the beginning of things, or asserting that God was always in bodily form before the world began. I do not say, I repeat, I do not say that the manhood was in God before it was born, but that God was afterward born in the manhood. For the flesh that was born of the flesh of the Virgin had not always existed; but God, who always was, came in human flesh, from the flesh of the Virgin. For “the Word was made flesh”: he did not bring flesh into view along with himself, but in the glory of his divinity he joined himself to human flesh.

Tell me, when or where was the Word made flesh? Where did he empty himself by taking the form of a servant? Where did he become poor, though he was rich? Where but in the holy womb of the Virgin? There, at his incarnation, the Word of God is said to have been made flesh. At his birth he truly took the form of a servant. And when he was nailed to the cross in his human nature, he became poor, and was made poor in his sufferings in the flesh, though he was rich in his divine glory.

Otherwise, if, as you say, the deity entered into him at some later time, as it entered one of the prophets and saints, then “the Word was made flesh” in those men also in whom he was pleased to dwell, and in each one of them he emptied himself and took the form of a servant. And so there is nothing new or unique in Christ. Neither his conception, nor his birth, nor his death had anything special or miraculous about it.