Question 22: Why must the Redeemer be truly human?
Answer: That in human nature he might on our behalf perfectly obey the whole law and suffer the punishment for human sin; and all
Therefore he had to be made like his brothers in every respect, so that he might become a merciful and faithful high priest in the service of God, to make propitiation for the sins of the people. Hebrews 2:17
Commentary by Athanasius of Alexandria
For the Word, perceiving that no otherwise could the corruption of men be undone save by death as a necessary condition, while it was impossible for the Word to suffer death, being immortal, and Son of the Father; to this end He takes to Himself a body capable of death, that it, by partaking of the Word Who is above all, might be worthy to die in the stead of all, and might, because of the Word which was come to dwell in it, remain incorruptible, and that thenceforth corruption might be stayed from all by the Grace of the Resurrection. Whence, by offering unto death the body He Himself had taken, as an offering and sacrifice free from any stain, straightway He put away death from all His peers by the offering of an equivalent. For being over all, the Word of God naturally by offering His own temple and corporeal instrument for the life of all satisfied the debt by His death. And thus He, the incorruptible Son of God, being conjoined with all by a like nature, naturally clothed all with incorruption, by the promise of the resurrection.
We human people are so fallen, and we’ve been so fallen for so long, that we actually think that we are the measure of what it means to be human. It’s striking. We say things like “to err is human.” And we unwittingly then begin to define humanity in terms of that fallenness, in terms of its brokenness, in terms of its incompleteness. But if you define humanity like that, what do you do with Jesus? What do you do with Jesus who takes upon himself our humanity, yet, as the Bible tells us, is without sin, who does not err?
What we see in Jesus is true humanity. What we see in his incarnation, his earthly life and ministry, is what humanity was meant to be, what Adam was created to be but ruined in his sin and his fall. So, as Romans 5 teaches, the first man Adam sins, and through his sin death enters the world. But here comes a second Adam, a true Adam, Christ, who is truly man. What Christ does in his humanity is nothing short of remarkable. In his humanity, he offers to God everything that we owe God. In his humanity, in his perfect obedience to God’s commands, he offers to God the obedience that we refuse to give him (and could not give him) because of our fallen, sinful nature.
It’s absolutely essential that what we see in Christ is perfect righteousness, because he’s supplying that righteousness on our behalf. All the righteousness we will ever need is in the Son of God who took upon himself our flesh, our likeness, our human nature. Not only does he positively supply the righteousness, but on the cross, our Savior dies and pays the penalty that humanity owed. He dies in our place. We owe God not only righteousness, but now because we didn’t supply that righteousness, we also owe God our lives, our death, our blood. Christ takes our place, and he supplies to God the sacrifice on our behalf that satisfies God’s demands for righteousness and his righteous determination to punish sin.
And so in order to be for us a perfect High Priest, in order to be for us a perfect offering, Jesus had to be one with us. He had to take upon himself our nature and in that nature demonstrate what humanity is, what it was meant to be—righteous before God, obedient to God, worshiping God in all things, loving him fully. And he also demonstrates what humanity owes when he pays the penalty on Calvary’s cross for our sin. And so to be that High Priest, a perfect High Priest, who also now sympathizes with us, knows our suffering, knows our failures, knows our troubles, and knows them intimately because he experienced them in our flesh, he can look to humanity with sympathy and represent humanity to God with perfection.
And so it was necessary that he be made like us in every way, but without sin.