Irenaeus of Lyons · a new plain-English translation from the original language
Had the flesh not been meant for salvation, the Word could never have assumed flesh sharing our own substance; otherwise our reconciliation through him could not have come to pass.
But because the Apostle was not disputing the underlying reality of flesh and blood themselves when he stated that such cannot inherit God's realm, this very Apostle elsewhere applies the phrase "flesh and blood" directly to the Lord Jesus Christ — in part to establish his true humanity, seeing that he named himself the Son of Man, and in part to guarantee that our flesh would indeed be rescued. Had flesh not been intended for rescue, the Word of God could never, in any manner, have become flesh at all; and had the blood of just men not been destined to be avenged, the Lord could never, in any manner, have possessed blood himself. Yet blood has carried a voice from the very first, as God told Cain once he had slain his brother: "Your brother's blood calls out to me from the ground." And because the blood of the righteous was appointed to be avenged, he told those who stood with Noah: "I will demand a reckoning for the blood of your lives from every beast." And further: "Whoever pours out the blood of a man, that man's own blood shall in turn be poured out." So too the Lord spoke, addressing those who were soon to pour out his own blood: "Every drop of innocent blood spilled upon the earth will be avenged — beginning with righteous Abel's blood and reaching to the blood of Zechariah son of Barachiah, murdered by you between the sanctuary and the altar. I tell you truly, all of this will fall upon the present generation" — thereby revealing that in his own person there would occur a gathering-up of the bloodshed of every righteous man and prophet since the beginning, and that a reckoning for their blood would be demanded through him. Yet no such reckoning could be demanded unless that blood were also destined for rescue; nor could the Lord have gathered these things into himself unless he had truly taken on flesh and blood according to man's original making, thereby rescuing within himself, at history's close, that which had been lost long ago in Adam.
But if the Lord took on flesh through some different scheme, drawing his body from a different substance, then he did not gather man up into himself, and could not truly be termed flesh in any real sense. For flesh is, in truth, nothing else than the ongoing continuation of that primal shaping out of clay. Yet had he needed to draw his matter from some other substance, the Father would from the outset have fashioned his whole composition out of that other substance instead. As matters stand, however, the Word became the deliverer of that very man who had gone astray, establishing fellowship with him and pursuing his rescue himself. Now the one who had gone astray was possessed of flesh and blood. For the Lord shaped man by taking clay out of the earth, and the entire design of the Lord's arrival was undertaken for that man's benefit. He himself, then, likewise possessed flesh and blood — no other kind, but that self-same lineage stretching from the first man, gathering into himself the Father's original handiwork, in pursuit of what had gone astray. It is for this reason that the Apostle, writing to the Colossians, states: "And you, once estranged and hostile in thought through wicked deeds, he has by now made peace with in the body of his flesh, through death, so as to set you before him holy, without fault, and beyond accusation." "In the body of his flesh," so he says, "made peace" — meaning that his own righteous flesh made peace with that flesh held captive by sin, drawing it into fellowship with God.
Now if someone claims that the Lord's flesh is unlike ours only in that his committed no sin and no falsehood was discovered in his heart, whereas we ourselves are sinners, he speaks truly. But should he instead attribute to the Lord an entirely separate kind of flesh, then the very notion of "making peace" no longer applies to him at all. For only what was once hostile can be brought back into peace. Yet if the Lord's flesh came from some other substance, then it was never the thing that had turned into God's enemy through wrongdoing that has now been reconciled. As things truly stand, though, through the fellowship he forged with us, the Lord has brought man back into peace with God the Father, reconciling us to himself by means of his fleshly body, and buying us back through his own blood — just as the Apostle writes to the Ephesians: "in whom we hold our ransom by way of his blood, namely the forgiveness of trespasses." And once more, to that same congregation: "You," he writes, "once distant, have now been drawn close through the blood of Christ." And further: "doing away, in his flesh, with the hostility, the law consisting of commandments expressed in decrees." Throughout this whole letter the Apostle openly attests that we owe our rescue to our Lord's flesh together with his blood.
Given, then, that flesh and blood are what grant us life, the statement was never truly aimed at flesh and blood in themselves as unfit for God's kingdom, but rather at those carnal practices mentioned earlier which, by pulling a man toward wrongdoing, rob him of life. This is likewise why, in writing to the Romans, he states: "Do not, then, let sin rule your mortal body so that you submit to its desires; do not offer your body's parts to sin as tools of wickedness, but offer yourselves to God as men brought to life out of death, and your body's parts to God as tools of righteousness." Just as we formerly served wrongdoing with these very limbs and produced a harvest leading to death, so now he wants us to serve righteousness with these same limbs, that we may produce a harvest leading to life. Bear in mind, then, dearest friends, that you were bought back through the flesh of our Lord and ransomed by his blood, and that you cling fast to the Head from which the entire body of the Church, knit together, grows — namely, the fleshly arrival of the Son of God — acknowledging him as God while fully embracing his human nature; and by drawing further on these scriptural proofs, you will readily, as already demonstrated, overturn every opinion later invented by the heretics.