st-irenaeus-of-lyonVain indeed are those who allege that He appeared in mere seeming. For these things were not done in appearance only, but in actual reality.

[…] And I have proved already, that it is the same thing to say that He appeared merely to outward seeming, and to affirm that He received nothing from Mary.

For He would not have been one truly possessing flesh and blood, by which He redeemed us, unless He had summed up in Himself the ancient formation of Adam.

Vain therefore are the disciples of Valentinus who put forth this opinion, in order that they may exclude the flesh from salvation, and cast aside what God has fashioned.

Vain also are the Ebionites, who do not receive by faith into their soul the union of God and man, but who remain in the old leaven of the natural birth.

They do not choose to understand that the Holy Ghost came upon Mary, and that the power of the Most High did overshadow her.

For this reason what was generated is a holy thing, and the Son of the Most High God the Father of all, who effected the incarnation of this being, showed forth a new kind of generation.

This happened so that, as by the former generation we inherited death, so by this new generation we might inherit life.

Therefore do these men reject the commixture of the heavenly wine, and wish it to be water of the world only. They do not receive God so as to have union with Him, but they remain in that Adam who had been conquered and was expelled from Paradise.

Yet, at the beginning of our formation in Adam, that breath of life which proceeded from God, having been united to what had been fashioned, animated the man, and manifested him as a being endowed with reason.

So also, in the times of the end, the Word of the Father and the Spirit of God, having become united with the ancient substance of Adam’s formation, rendered man living and perfect, receptive of the perfect Father, in order that as in the natural Adam we all were dead, so in the spiritual we may all be made alive.

For never at any time did Adam escape the hands of God, to whom the Father speaking, said, “Let Us make man in Our image, after Our likeness.”

And for this reason in the last times, not by the will of the flesh, nor by the will of man, but by the good pleasure of the Father, His hands formed a living man, in order that Adam might be created again after the image and likeness of God.

Irenaeus of Lyons (2nd century AD – c. 202): Adversus Haereses, 5, 1, 2-3.