But when Jesus turns to them again he calls special attention to the main source of their continuous misconception and rejection. Not only is he "the Son," and "the Son of God," but indubitably he is also "the Son of man."
He has come down from heaven and is before them as a Man among men—"one Jesus." He has taken upon himself the form of a slave, the fashion of man. That the manifestation of the Divine should be perfectly realized in the human, though a fundamental truth lying at the heart of all revelation, is nevertheless not the alphabet of Divine teaching; nay, it is the very highest and most recondite of all truths.
This humbled humanity of the incarnate Logos led on to other issues of enormous significance. The eternal Son in the form of God would become, as "Son of man," obedient unto death. The highest revelation of the Son of God, and therefore of the Father, would be effected by the surrender of that mysterious life of his for the world's behoof.
The previous announcements of this truth, which we now see to be the very crown and culmination of the gospel, had greatly offended his hearers of all kinds, and on distinct grounds. In the words that follow a touch of deeper meaning than any which had preceded is supplied when he proceeds to associate this death of the Son of man with the wilful act of the ecclesiastical authorities in Jerusalem.
Jesus therefore said (unto them £), When ye shall have lifted up the Son of man (compare here notes on John 3:14; John 6:62; John 12:32). The word ὑψόω is used with the twofold sense of exaltation on the cross'' signifying by what death he should glorify God"—and also of the issues of that lifting up by means of the tree of ignoble torment and mortal agony to the throne of glory.
The twofold meaning of the word cannot be excluded here. £ Then ye shall come to know—then the process of proof will be completed—that I am (he)—that I am that which fundamentally I am declaring to you, that my testimonies have unique but trenchant confirmation £—and that I am doing nothing from myself, but that even as the Father taught me, (so) these things I speak.
The "he that sent me" (John 8:26), is here replaced by "the Father." "The things which I heard from ( παρὰ) him" is replaced by "even as the Father taught me," and the ταῦτα λαλῶ are repeated. "The cross and the crown" will be the proof to the most obtuse and bigoted "that I am that which I say I am."
The forecast is here given of the conversion of his murderers, the overwhelming effects produced by the resurrection and the ascension of Jesus, and the gift of the Holy Ghost (Acts 2:36; Acts 4:4; Acts 6:7; Romans 11:11).
Bengel: "Cognoscetis ex re, quod nunc ex verbo non creditis."