Having fulfilled his mission, providing the Way, the means of conquering the world, it should not come as a surprise that John 17 opens with Jesus’ prayer and surrender to ultimate sacrifice: “Father, the hour has come; glorify your Son so that the Son may glorify you” (1). Verse two then establishes Jesus’ authority: “You have given him authority over all people.”  And what is that authority? “To give eternal life to all whom you have given him” (2). And what is eternal life? “This is eternal life, that they may know you, the only true God, and Jesus Christ whom you have sent” (3).  And how does Jesus establish his claim to the Father? “I glorified you on earth by finishing the work you gave me to do” (4).  Even in modern existential literature, even without a God, what more noble calling for humanity than commitment to, and carrying through on the one real choice—to complete the life-work given to us, perhaps unasked for, in some cases, unwanted; perhaps it is true that the individual stands on a precipice and decides in dizziness whether to jump or stay. Is this, in fact, the temptation of Jesus?  Is Jesus, then, in some way, as the Greeks suggested, the ideal human being, and in being ideal, does he in some way then escape and become more than human—in some way both God and human? This would be a metaphorical way of speaking about Jesus. John certainly proclaims Christ God! This is the witness Jesus charged his disciples with in chapter sixteen, a mission carried out that secures them as God's children, hated by the world as was Jesus.

            John returns to his beginning: “In the beginning was the Word.”  Hear his next words in chapter seventeen:

6 “I have made your name known to those whom you gave me from the world. They were yours, and you gave them to me, and they have kept your word.  7 Now they know that everything you have given me is from you;  8 for the words that you gave to me I have given to them, and they have received them. 

Larry Richards in Every Prayer in the Bible provides lengthy commentary on Jesus' prayer for his disciples in chapter seventeen. He identified prayer for the glorification of the Son that He might be the source of life, prayer for his disciples that they be kept and sanctified, and that all believers might be one, and that believers might be with him.

The Intervarsity Commentary points out that chapter seventeen contains the most extensive and profound prayer of Jesus commonly recognized as the high priestly prayer:

Jesus' intercession for his disciples from within God's presence anticipates his role after his ascension (cf. 1 Jn 2:1). Because this intercession corresponds to the role of the high priest elsewhere in the New Testament (Rom 8:34; Heb 7:25-26) and because Jesus uses sacrificial language when he refers to sanctifying himself (17:19), this prayer has been known as the High Priestly Prayer. In the fifth century Cyril of Alexandria saw these two activities as fitting for the one who is "our great and all-holy High Priest" (In John 11.8).

The chapter echoes themes of earlier chapters (faith, knowledge, love, indwelling, oneness and God's name. There is also an emphasis on the world, including its separation from God, God's love for it and the disciples' mission to it) and outlines a complex structure containing a petition for glory, prayer for the disciples, and a prayer that all will become one;

As with much of the farewell discourse, this material is complex and can be outlined in several ways (cf. Brown 1970:748-51; Beasley-Murray 1987:295-96). Jesus begins with a petition for the glorification of the Father and the Son (vv. 1-5), after which he prays for the disciples gathered around him, first describing their situation (vv. 6-11) and then praying that they be protected and sanctified by God (vv. 11-19). Jesus then prays for all who will become believers through the witness of the eleven, that they may share in the divine oneness (vv. 20-24). He concludes with a summary of his past and future work (vv. 25-26).

      What does knowing the Word mean?

[They]know in truth that I came from you; and they have believed that you sent me.  9 I am asking on their behalf; I am not asking on behalf of the world, but on behalf of those whom you gave me, because they are yours.  10 All mine are yours, and yours are mine; and I have been glorified in them. 

And what is it that Jesus asks for his followers—only protection!             

11 And now I am no longer in the world, but they are in the world, and I am coming to you. Holy Father, protect them in your name that you have given me, so that they may be one, as we are one.  12 While I was with them, I protected them in your name that † you have given me. I guarded them, and not one of them was lost except the one destined to be lost, † so that the scripture might be fulfilled.

It has been the mission of Jesus to protect, but now, bracing for the ultimate sacrifice, he prays for continuing protection, recognizing that “not one” under his care “has been lost except the one destined to be lost.”  Consider Judas.  And why was the one lost? “so that the scripture might be fulfilled.”

            And what is the ultimate mission of Jesus, indirectly the mission taken up by Christianity?

20 “I ask not only on behalf of these, but also on behalf of those who will believe in me through their word,  21 that they may all be one. As you, Father, are in me and I am in you, may they also be in us, † so that the world may believe that you have sent me.  22 The glory that you have given me I have given them, so that they may be one, as we are one,  23 I in them and you in me, that they may become completely one, so that the world may know that you have sent me and have loved them even as you have loved me.  

The notion of unity here is theologically tied to the indwelling of the Father and the Son:

In the first century there was a widespread belief among Jews, Greeks and Romans in the unity of humanity. Various sources for this unity were suggested, including the concept of one God, the recognition of one universal human nature, the recognition of a universal law and the notion of one world (Taylor 1992:746-49). Efforts were made to embody this unity. For example, Alexander the Great had set out to unite the inhabited world, and later the Romans picked up the same goal. On a smaller scale, the members of the community at Qumran referred to themselves as "the unity," which included a unity with the angels, thus linking heaven and earth (Beasley-Murray 1987:302). So Jesus' prayer would speak to an issue of great interest, but the oneness he refers to is distinctive in its nature from other notions of unity. It is grounded in the one God, as were some other views of unity (Taylor 1992:746), but also in himself and his own relation with the one God. He claims to offer the unity that many were desiring, but this unity is grounded in his own relation with his Father. Furthermore, he says that the band of disciples there in the room with him is the nucleus of the one unified humanity.

Jesus speaks of the oneness of all believers (that all of them may be one, v. 21) and then links this with the mutual indwelling of the Father and the Son. The NIV has this indwelling as the model for the relationship among believers: just as you are in me and I am in you. The word translated just as (kathos) can signal not only comparison but cause. Both of these two meanings are appropriate here, for the mutual indwelling of the Father and the Son is both the reason that all may be one and the pattern for such oneness. This becomes clearer when Jesus adds "that they themselves also may be in us" (v. 21; the NIV makes this a new sentence). The oneness of believers is to be found in us, in their relation to the Father and the Son. The same twofold thought occurs when Jesus repeats that they may be one as [kathos] we are one (v. 22). The oneness of the Father and the Son is both the cause of and the model for the believers' unity.
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What ultimate destiny awaits those who follow him? They ultimately are to be glorified, as Jesus is glorified, in the presence of God:

24 Father, I desire that those also, whom you have given me, may be with me where I am, to see my glory, which you have given me because you loved me before the foundation of the world.

11      “Righteous Father, the world does not know you, but I know you; and these know that you have sent me.  26 I made your name known to them, and I will make it known, so that the love with which you have loved me may be in them, and I in them.”

Where “I am…”  The reader will recall this pattern:

1. The bread of life (6:35).
2. The light of the world (8:12; 9:5).
3. The door of the sheepfold (10:7).
4. The good shepherd (10:11,14).
5. The resurrection and life (11:25).
6. The way, truth and life (14:6).
7. The true vine (15:1).

As so often with John, theology exists in every utterance; Nelson's New Illustrated Commentary captures the sublimity of theology. For Jesus, the hour alluded to throughout John has come, his mission to the world to be completed, a mission revealing God's love and justice. Jesus will complete his work glorifying the Father with the Father glorifying him. The disciples will continue the work of glorification. Believers must pray for present and future believers. This prayer "keeps" believers true to the revelation of God provided by Jesus. Praying aloud comforts disciples who must remain "in the world," although "not of the world." Already a part of God's Kingdom, followers of Jesus are sanctified and set apart, kept from evil in order to advance in holiness. As Christ committed fully to self-sacrifice, so must believers, present and future. Unity, illustrated in the true vine of chapter fifteen, takes place through sanctification and loving relationship. An indwelling Father, Son, and Spirit reveal deity, its full revelation leading to glorification.

17:25, 26 Jesus concludes His prayer, summarizing several of the main themes: (1) knowing the righteous (holy) God; (2) Jesus’ divine origin; (3) the revealing of the Father’s name; and (4) the unity of mutual love between the Father, Son, and believers.

Radmacher, E. D., Allen, R. B., & House, H. W. 1999. Nelson's new illustrated Bible commentary . T. Nelson Publishers: Nashville