John Calvin Commentary John 6:62

"[What] then if ye should behold the Son of man ascending where he was before?" — John 6:62 (ASV)

What if you will see the Son of man ascend to where he was before? The lowly and despicable condition of Christ, which they saw before their eyes while, clothed in flesh, he was not at all different from other men, prevented them from submitting to his Divine power.

But now — by withdrawing the veil, as it were — he calls them to behold his heavenly glory, as if he had said, “Because I live among men without honor, I am despised by you, and you recognize in me nothing that is Divine; but soon God will adorn me with splendid power, and, withdrawing me from the contemptible state of mortal life, will raise me above the heavens.”

For, in the resurrection of Christ, so great was the power displayed by the Holy Spirit, that it plainly showed Christ to be the Son of God, as Paul also shows (Romans 1:4). And when it is said,

You are my Son, today I have begotten you,
(Psalms 2:7),

the resurrection is brought forward as a proof from which that glory of Christ should be acknowledged, and his ascension to heaven was the completion of that glory. When he says that he was formerly in heaven, this does not apply strictly to his human nature, and yet he speaks of the Son of man; but since the two natures in Christ constitute one person, it is not an unusual way of speaking to transfer to one nature what is peculiar to the other.