LORD’S DAY 14
35. What is the meaning of “conceived by the Holy Spirit, born of the virgin Mary?”
That the eternal Son of God, who is1 and continues true and eternal God,2 took upon Himself the very nature of man, of the flesh and blood of the virgin Mary,3 by the operation of the Holy Spirit;4 so that He might also be the true seed of David,5 like unto His brethren in all things,6 except for sin.7
 Jn. 1:1; Rom. 1:3–4.  Rom. 9:5.  Gal. 4:4; Jn. 1:14.  Matt. 1:18–20; Lk. 1:35.  Ps. 132:11.  Phil. 2:7.  Heb. 4:15; *1 Jn. 5:20.
36. What benefit do you receive from the holy conception and birth of Christ?
That He is our Mediator,1 and with His innocence and perfect holiness covers, in the sight of God, my sin, wherein I was conceived.2
 Heb. 2:16–17.  Ps. 32:1; *1 Jn. 1:9.
Redeeming all that He Assumed
The Incarnation of Christ is one of the most vitally important doctrines of Christianity. The gospel itself stands or falls with it.
In the long debates about the exact nature of the incarnation of Christ, Gregory of Nazianzus said, “What is not assumed is not redeemed.” This quote brilliantly shows the need for Christ to have adopted the whole nature of humanity in the incarnation, and also helps us understand what it is Jesus accomplished in the incarnation.
“Incarnation” refers to Jesus becoming a real and true human being, and as a true human being, He lived a life of perfect obedience and died the death of a sinner, the death we deserved. The wrath of God against sinners will be exercised against the whole human being, body and soul, and therefore Christ suffered as a whole human being, body and soul. In addition to the obvious physical suffering He experienced on the cross, we also see Him crying out, “My God, My God, why have you forsaken Me?” But how could the second Person of the Trinity, eternally coexisting with the other two Persons in one divine Essence, ever be separated from God? He IS God. And His cry here is not the cry of merely physical suffering, but spiritual suffering as well. Only if He possessed a true human nature could He experience anything like this.
But this goes beyond the suffering He experienced on the cross, but also to His life. As question 36 says, it was His innocence and perfect holiness which covers me in God’s sight. Jesus lived a life of innocence and holiness, and in doing so He positively fulfilled the demands of the law of God and “covered” (q. 36) my failure to do so. He was what a man is supposed to be, a perfect servant of God, bringing glory and honor to the Father’s name. Jesus did this throughout His life, even to His death. He “became obedient unto death, even the death of the cross.” (Phil. 2:8) In doing so He redeems the very idea of humanity. He proves that God didn’t make a mistake in making us, that a human being could be a perfect servant of God. He fulfilled the “righteous requirement of the law” (Romans 8:4) on our behalf, so that our salvation is truly complete in Him with nothing left for us to add.
He is truly a complete Savior. I can rest easy that the demands of God’s law are perfectly met, and the curse of sin has no more hold on me. Further, His perfect human life is now communicated to me by the Holy Spirit so that His righteousness will be worked in me, to conform me to His image. If He is the perfect human, then being made like Him means that I will become a perfect human as well. All my sorrows, all my failures, all my weaknesses will one day be gone, and all the things I long for as a human being will be achieved. Following Him now, striving to be like Him, is simply fulfilling my reason to exist and attaining my true nature. Repenting from sin is merely being rid of an infection that is foreign to me, a slavery that is against me.
If Jesus is not both fully human and fully divine, then we cannot say this. As Gregory of Naziansus said, whatever is not assumed is not redeemed. Unless Jesus was fully human, I can have no confidence that all of the obedience that I as a human being owe to God was achieved by Him on my behalf, and no confidence that all of the punishment due to me for my failure in both body and soul to obey God’s law was suffered by Him in my place. With this precious doctrine of the incarnation, though, I can have total confidence in my perfect redemption, and joy and hope in my ongoing and future restoration in Him.