Why is Jesus' Humanity Crucial to the Christian Faith?
Jesus’ humanity is tightly fixed with his relatability. There is nothing spectacular about a divine being who is capable of healing, performing, and raising from the dead. In fact, impassibility and immortality is the nature of God. Jesus’ humanity serves as the mediation between the divine and man. For if Christ had only performed his miracles by the “indwelling” of the divine, he would have been nothing greater than a prophet, who did the same. From the words of Nestorius as he argued this point to Leo at the Second Council of Constantinople in 553:
Who is it that walked on the water? It was the feet that walked, and the concrete body through the power that dwelt in him. That is a miracle. For if God walks on the water, that is not amazing. - Archbishop of Constantinople, Nestorius
The miracle rests not in the act itself, but from the one who possess the ability to conjure the power of the divine through the body of a man. “In the womb of Mary the Infant was formed, who from eternity is equal to the Father.” Jesus was born into a feeble body like all of humanity, with vulnerable hands that still touched lepers; it was his back that was lashed, this feet that were pierced, and his side that was speared. Jesus experienced unimaginable torment at the end of his life and devilish temptation throughout it. The miracle of the incarnation was not in God’s ability to do it, but in his willingness.
Who, though he was in the form of God, did not consider equality with God as something to be exploited, but emptied himself, taking the form of a slave, being born in human likeness. And being found in human form, he humbled himself and became obedient to the point of death--even death on a cross. - Philippians 2:6-8.
It is difficult for any singular theology regarding the incarnation to encompass fully the totality of the divine as human. For example Theodore of Mopsuestia challenges this by saying, “the deity was separated from him who suffered according to the experience of death, for it was not possible for it [the deity] to undergo the experience of death.” You would imagine that the New Testament would answer such a profound theological stance on the incarnation, but the transmission and translation of the biblical text proved to have its resilience. For example, there are the two Syriac translations of Hebrews 2:9 which read differently: "Because he, God, by his grace tasted death for every man," while the other read, "Apart from God he [Jesus] tasted death." The one preserves the oneness of the divine and the man, while the other preserved the possibility of the divine, especially in death.
Certainly it is instances like this that muddy the water of our understanding of the incarnation of God. However, despite the infrequent gray areas of this issue, there is an overwhelming necessity for Jesus to be fully human. The majesty of God needed to assume the lowliest position; power needed to be subsided by weakness, and ultimately mortality needed to win over eternity. This was the meaning of the Gospels which hold evidence of the humanity of Jesus juxtaposed with proofs of his divine capabilities. Jesus was everything like humankind while be nothing like us, having lived without sin (Hebrews 4). The model of Jesus’ life gives us the footprints to walk after. However, without the feet of a man, there would be no footprints for us to follow. God, through the form of a man, walk with his creation in order to save and guide his creation along the path of righteousness. Jesus’ humanity is tightly fixed with his relatability.