Irenaeus

For this reason [it is, said], "Who shall declare His generation?" since "He is a man, and who shall recognise Him?" But he to whom the Father which is in heaven has revealed Him, knows Him, so that he understands that He who "was not born either by the will of the flesh, or by the will of man," is the Son of man, this is Christ, the Son of the living God. For I have shown from the Scriptures, that no one of the sons of Adam is as to everything, and absolutely, called God, or named Lord. …

Against Heresies 3:19.2 ↗

Augustine of Hippo

On hearing this curse pronounced in the figurative language of prophecy on him that trusts in man, and the blessing in similar style on him that trusts in God, the inquirer might have doubts about our doctrine, in which we teach not only that Christ is God, so that our trust is not in man, but also that He is man because He took our nature. So some err by denying Christ's humanity, while they allow His divinity. …

Reply To Faustus The Manichaean 13:8 ↗

Ambrose of Milan

The apostle says, "For God, sending his own Son in the likeness of sinful flesh, and for sin condemned sin in the flesh, that the righteousness of the law might be fulfilled in us." He does not say "in the likeness of flesh," for Christ took on himself the reality, not the likeness, of flesh. Nor does he say in the likeness of sin, for he did not sin but was made sin for us. …

Concerning Repentance 1.3.12 ↗

Jerome

The heart of all is perverse and inscrutable, who can understand it? I am the Lord, searching the heart and testing the kidneys, who gives to each according to their ways and according to the fruit of their inventions. LXX: The heart is deep above all, and man is, who can know him? and so on. The Hebrew word Enos is written with four letters, Aleph and Nun and Vau and Sin. Therefore, if Enos is read, it means 'man', but if Anus, it is inscrutable or desperate, because no human heart can find it. …

Commentary on Jeremiah ↗