John 3:12–15

Verse 13. No man hath ascended—but he that descended from heaven, the Son of man, who is in heaven. These words, divers times repeated by our Saviour, in their literal and obvious sense, shew that Christ was in heaven, and had a being before he was born of the Virgin Mary, against the Cerinthians, and so forth That he descended from heaven: that when he was made man, and conversed with men on earth, he was at the same time in heaven. Some Socinians give us here their groundless fancy, that Jesus after his baptism took a journey to heaven, and returned again before his death. Nor yet would this make him in heaven, when he spoke this to his disciples. Witham.

Verse 14. This comparison of the serpent lifted up in the desert, upon which whoever looked was immediately cured from the bite of the fiery serpents, is a figure of the crucifixion of Christ on Calvary. And we remark, that our divine Saviour makes use of these words, the Son of man must be lifted up or exalted; (exaltari) by which form of expression he would teach us, that he does not consider the cross as a disgrace, but as a glory; (Theo. and Saint John Chrysostom) and moreover, that as the Israelites, bitten by the fiery serpents, were cured by looking upon the brazen serpent, so are Christians cured by looking up with an active faith, replete with love and confidence, on Jesus Christ crucified.