“Then said Jesus unto them, When ye have lifted up the Son of man, then shall ye know that I am he, and that I do nothing of myself; but as my Father hath taught me, I speak these things.”
Then said Jesus unto them, When ye have lifted up the Son of man, then shall ye know that I am he, and that I do nothing of myself; but as my Father hath taught me, I speak these things — Jesus predicts the crucifixion ('when ye have lifted up the Son of man,' a veiled reference to his being lifted up on the cross), claiming that this event will produce recognition. 'Then shall ye know that I am he'—the crucifixion, rather than defeating Jesus's claim, will vindicate it. Those who witness his lifting up will recognize his identity. The continuation emphasizes again that Jesus does nothing of himself but speaks what the Father has taught him. The crucifixion becomes the supreme moment of revelation: lifted up, Jesus reveals God's love and truth.
Church Fathers on John 8:28
When our Lord said, He is true that sent Me, the Jews did not understand that He spoke to them of the Father. But He saw some there, who, He knew, would believe on Him after His passion. Then said Jesus to them, When you have lifted up the Son of man, then you shall know that I am. Recollect the words, I am that I am, and you will know why I say, I am. I pass over your knowledge, in order that I may fulfill My passion. In your appointed time you will know who I am; when you…
When His miracles and teaching had failed to convert men, He spoke of the cross; When you have lifted up the Son of man, then you shall know that I am He: as if to say, you think that you have killed Me; but I say that you shall then, by the evidence of miracles, of My resurrection, and your captivity, know most especially, that I am Christ the Son of God, and that I do not act in opposition to God; But that as My Father has taught Me, I speak these things. Here He shows the…