Frpm John 8:21-30
Jesus Warns the Unbelieving Jews
 Again He (Jesus) said to them, "I go away, and you will seek Me and die in your sin; where I am going, you cannot come."  Then said the Jews, "Will He kill Himself, since He says, `Where I am going, you cannot come?'"  He said to them, "You are from below, I am from above; you are of this world, I am not of this world.  I told you that you would die in your sins, for you will die in your sins unless you believe that I am He."  They said to Him, "Who are You?" Jesus said to them, "Even what I have told you from the beginning.  I have much to say about you and much to judge; but He who sent Me is true, and I declare to the world what I have heard from Him."  They did not understand that He spoke to them of the Father.  So Jesus said, "When you have lifted up the Son of Man, then you will know that I am He, and that I do nothing on My own authority but speak thus as the Father taught Me.  And He who sent Me is with Me; He has not left Me alone, for I always do what is pleasing to Him."  As He spoke thus, many believed in Him.
21-24. At the outset of His public ministry, Jesus could be seen to have all the features of the promised Messiah; some people recognized Him as such and became His followers (cf. John 1:12-13; 4:42; 6:69; 7:41); but the Jewish authorities, although they were expecting the Messiah (cf. John 1:19ff), persisted in their rejection of Jesus. Hence the warning to them: He is going where they cannot follow, that is, He is going to Heaven, which is where He has come from (cf. John 6:41ff), and they will keep looking out for the Messiah foretold by the prophets; but they will not find Him because they look for Him outside of Jesus, nor can they follow Him, for they do not believe in Him. You are of the world, our Lord is saying to them, not because you are on earth but because you are living under the influence of the prince of this world (cf. John 12:31; 14:30; 16:11); you are his vassals and you do his deeds (cf. 8:44); therefore, you will die in your sin. "We are all born with sin", St. Augustine comments, "all by our living have added to what we were by nature, and have become more of this world than we then were, when we were born of our parents. Where would we be if He had not come, who had no sin at all, to loose all sin? The Jews, because they did not believe in Him, deserved to have it said to them, 'You will die in your sin'" ("In Ioann. Evang.", 38, 6).
The salvation which Christ brings will be applied to those who believe in His divinity. Jesus declares His divinity when He says "I am He", for this expression, which He repeats on other occasions (cf. John. 8:28; 13:19), is reserved to Yahweh in the Old Testament (cf. Deuteronomy 32:39; Isaiah 43:10-11), where God, in revealing His name and therefore His essence, says to Moses "I AM WHO I AM" (Exodus 3:14). In this profound way God says that He is the Supreme Being in a full, absolute sense, that He is dependent on no other being, that all other things depend on Him for their being and existence. Thus, when Jesus says of Himself, "I am He", He is revealing that He is God.
25. A little before this Jesus had spoken about His Heavenly origin and His divine nature (cf. verses 23-24); but the Jews do not want to accept this revelation; which is why they ask Him for an even more explicit statement: "Who are You?" Our Lord's reply can be understood in different ways, because the Greek text has two meanings: 1) our Lord is confirming what He has just asserted (cf. verses 23-24) and what He has been teaching throughout this visit to Jerusalem--in which case it may be translated "precisely what I am telling you" or else "in the first place what I am telling you". This is the interpretation given in the New Vulgate. 2) Jesus is indicating that He is the "Beginning", which is the word St. John also uses in the Apocalypse to designate the Word, the cause of all creation (Revelation 3:14; cf. Revelation 1:8). In this way Jesus states His divine origin. This is the interpretation given in the Vulgate. Either way, Christ is once more revealing His divinity; He is reaffirming what He said earlier, but without saying it all over again.
"Many people in our own days ask the same question: 'Who are You?' [...] Who, then, was Jesus? Our faith exults and cries out: it is He, it is He, the Son of God made man. He is the Messiah we were expecting: He is the Savior of the world, the Master of our lives: He is the Shepherd that guides men to their pastures in time, to their destinies beyond time. He is the joy of the world; He is the image of the invisible God: He is the way, the truth and the life; He is the interior friend; He is the One who knows us even from afar; He knows our thoughts; He is the One who can forgive us, console, cure, even raise from the dead; and He is the One who will return, the judge of one and all, in the fullness of His glory and our eternal happiness" (Paul VI, "General Audience", 11 December 1974).
26-27. "He who sent Me": an expression very often found in St. John's Gospel, referring to God the Father (cf. 5:37; 6:44; 7:28; 8:16).
The Jews who were listening to Jesus did not understand whom He was referring to; but St. John, in recounting this episode, explains that He meant His Father, from Whom He came.
"He spoke to them of the Father": this is the reading in most of the Greek codexes, including the more important ones. Other Greek codexes and some translations, including the Vulgate, read, "He was calling God His Father."
"What I have heard from Him": Jesus had connatural knowledge of His Father, and it is from this knowledge that He speaks to men; He knows God not through revelation or inspiration as the prophets and sacred writers did, but in an infinitely higher way: which is why He can say that no one knows the Father but the Son and He to whom the Son chooses to reveal Him (cf. Mt 11:27).
On the type of knowledge Jesus had during His life on earth, see the note on Luke 2:52.
28. Our Lord is referring to His passion and death: "`And I, when I am lifted up from the earth, will draw all men to Myself'. He said this to show by what death He was to die" (John 12:32-33). Rounding out the Synoptics and the Letters of St. Paul, the Fourth Gospel presents the Cross, above all, as a royal throne on which Christ is "lifted up" and from which He offers all men the fruits of salvation (cf. John 3:14-15; cf. also Numbers 21:9ff; Wisdom 16:6).
Jesus says that when that time comes, the Jews will know who He is and His intimate union with the Father, because many of them will discover, thanks to His death and resurrection, that He is the Messiah, the Son of God (cf. Matthew 15:39; Lk 33:48). After the coming of the Holy Spirit many thousands will believe in Him (cf. Acts 2:41; 4:4).
Source: "The Navarre Bible: Text and Commentaries". Biblical text taken from the Revised Standard Version and New Vulgate. Commentaries made by members of the Faculty of Theology of the University of Navarre, Spain. Published by Four Courts Press, Kill Lane, Blackrock, Co. Dublin, Ireland. Reprinted with permission from Four Courts Press and Scepter Publishers, the U.S. publisher.