The Lord took for granted that the 11 would preach the word (17:20), do you? If you’re thinking more people would believe if you could do miracles as they could (Acts 2:41-43), think again (Mt. 11:20).
Our Calvinist friends don’t pray for the “non-elect” since Christ only prayed for believers and future believers (17:20), not for the world (17:9). But He didn’t pray for the world because He knew God’s plan to reach the world was through the Jews, so He prayed for the 11 Jews He was about to send to the world (Mr. 16:15). Paul prayed for the unsaved (Rom. 10:1) and so should we.
“Them also which shall believe on Me through their word” (v. 20) was not us Gentiles, as the commentaries say. You didn’t believe on Christ through the word of the 12, you believed on Christ through the word of Paul, even if you were saved through John 3:16. You have to read Paul’s gospel (I Cor. 15:1-4) into the four gospels, for it isn’t there.
The 11 preached their words at Pentecost, and men believed through their words (Acts 4:4). But Peter was addressing only Jews (Acts 2:14, 22, 36), so they were all Jews! So why did the Lord pray that Jews would be “one” (Jo. 17:21)? The commentaries say that’s the coming together of Jews and Gentiles in the Body (Eph. 2:12-14), but this can’t be, for they were all Jews! But the two houses of Israel were divided, and needed to be made “one stick” (Ezek. 37:15-22), and this is what the Lord prayed for. His prayer was answered when they were made one at Pentecost (Acts 2:41-46). He wanted them made one “that the world may believe” (Jo. 17:21), and someday in the kingdom of heaven on earth they will!
If the 11 were going to be as one as the Father and Son (17:21) they’d need help (Mt. 20:21; Mark 9:33). Seeing this, the Lord gave them the glory the Father gave Him (v. 22), i.e., His glorious word (John 17:8). The Word can do some glorious things, like save a man’s soul and teach him how to cleanse his ways (Ps. 119:9). Our oneness is also based on the Word (I Cor. 1:10), being of “the same mind,” i.e., “the mind of Christ” that we have in the Word (I Cor. 2:16).
When this Word was written on their hearts at Pentecost (Jer. 31:34), it made them one like no other people in history have ever been one, as one as the Father and Son. Since the Lord was in them and the Father was in Him (Jo. 17:23), when they were filled with the Spirit they were filled with the entire Godhead. This made them “perfect in one” (v. 23). Noah was “perfect in his generations” (Gen. 6:9), God is “perfect in knowledge” (Job. 36:4; 37:16), Satan was “perfect in all thy ways” (Ezek. 28:15), but the saints at Pentecost were “perfect in one,” i.e., in unity. When that happened, the Lord said that the world would know “that Thou hast sent Me” (Jo. 17:23 cf. John 13:35).
When the Lord prayed that His disciples would be with Him where He was (Jo. 17:24), we know He didn’t mean in Paradise (Lu. 23:43), for they couldn’t “behold My glory” there (Jo. 17:24). He was praying that they would be with Him in the kingdom prepared for Him “before the foundation of the world” (Jo. 17:24 cf. Mt. 25:34).
The Father promised believers they’d be in that kingdom (Jo. 6:39, 40) and so would be unrighteous if they didn’t make it, so the Lord reminded the Father He was too “righteous” to break His word (Jo. 17:25). He called on God to keep His word, just as Moses called on Him to keep His word to Abraham (Ex. 32:10-14).
Knowing that the Father sent Him (Jo. 17:25) was all they had to believe to be saved (Jo. 17:25). How’d they know it? The Lord “declared” the Father’s name to them (v. 26) by doing all the Father told Him to do, and then ascribing those works to the Father (Jo. 14:10). When the Lord said He would declare His name again (Jo. 17:26), He meant by doing the last thing the Father asked Him to do: die for them, “that the love wherewith Thou hast loved Me may be in them” (Jo. 17:26). It was true of them, and it is true of us! Because the Son was “obedient unto death” (Phil. 2:8), the Father loves us as He loves His own Son! Glory!