"Neither pray I for these alone, but for them also which shall believe on me through their word; That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me." John 17:20,21
We hear this quoted often, and alluded to even more often. Almost never do we actually hear the full quotation. This should not be surprising in an age that thinks in sound bites, and that places greater emphasis on how people feel about issues, than on what they think about them. When we are treated to these allusions and partial quotations, the message seems to be this: Jesus really wants us to become one, and we have to make it happen. Put another way, God is praying to us, and we ought to hear his prayer.
And, if that seems wrong to you, good; well it should.
The emphasis of the Gospel according to St. John is twofold: It is the Trinity and the Incarnation. As it opens, John takes us behind the scenes of Genesis. The Hebrew name of the first book of the Bible means, "In the beginning." ( B'Rasheet, בְּרֵאשִׁית). John opens with this same phrase recognized by readers of the Septuagint (LXX), the standard Greek translation of the Old Testament; He too opens with, "In the beginning," (En Arche, ἐν ἀρχῇ ). In the Book of B'Rasheet, or Genesis, we are told what God did, the word "created" (bora, בָּרָא) following as the second word ("In the beginning" is all one word). If translated into English words, but retaining Hebrew syntax, it would say, "In the beginning created God the heavens and the earth." The emphasis is not on God himself, but on his work of creation. John, using the expression known to Greek readers of the LXX (ἐν ἀρχῇ ) alludes to the opening of Genesis in a very obvious way, but does not immediatley speak of God's work. First he lingers on God as God, and presents God as the Trinity.
"In the beginning was the Word (Logos, Λόγος), and the Word was with God, and the Word was God. The same was in the beginning with God." (1:1,2)
Verse 2 is not superflous; it mentions God the third time because, as this Gospel unfolds, we see the Son and we hear him speak of the other Comforter, that is the Spirit of Truth. The theme of God as Trinity is presented immediately. Then, with a bow to the Genesis narrative, John speaks of creation (בָּרָא): "All things were made by him; and without him was not any thing made that was made. " He speaks of the Logos as the One in whom there is life, that is, life that gives life, suggesting most strongly the creation of Man: "In him was life; and the life was the light of men." When we keep reading, and get to verse 14, the second great theme of John's Gospel is introduced. "And the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth."
It is only in the context of these two great themes that dominate this Gospel, the Trinity and the Incarnation of the Word, that we have any business interpreting the meaning of the High Priestly prayer of chapter 17. The first Unity that we must consider in the words of this prayer is the Unity of the Trinity. So, it opens: "These words spake Jesus, and lifted up his eyes to heaven, and said, Father, the hour is come; glorify thy Son, that thy Son also may glorify thee: As thou hast given him power over all flesh, that he should give eternal life to as many as thou hast given him. And this is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou hast sent. " (17:1-3) Our salvation is knowing God, and because whoever sees the Son sees the Father, and no man comes to the Father but by the Son (14:6-10), because God cannot be separated from God (for each Person is distinct, but inseparable), to know the Father requires that we know Jesus Christ. The only true God is known truly only by revelation, namely, Jesus Christ Whom he has sent; that is, the Word Incarnate.
By the time we get to the place where Jesus says, "Holy Father, keep through thine own name those whom thou hast given me, that they may be one, as we are" (v.11), it ought to be clear that he is speaking to the Father, one Divine Person to another Divine Person, about our common salvation in himself. The meaning is eternal and salvific. It means, in effect, keep them in me. For, "this is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou hast sent. "
Understood correctly, "that may all be one" gives greater motivation to be unified among ourselves in common faith and thought, with charity; because we are one whether we live like it or not. A prayer spoken within the Godhead, which we are privileged to overhear, the Son addressing the Father, is as much a declaration as "Let there be light," or "Let us make man in our image." God has pronounced that his people are one, that is, that the Church is, as St. Paul says many times, "in Christ." The Church as a whole is "in Christ," and each member of the Church is "in Christ."
We know that a married couple is no longer two, but one flesh. This is clear in Genesis, in the Gospels where Jesus explains that divorce is a mere fiction, and in the Epistles of Paul when he warns us to live within the boundaries of God's moral laws. To suggest that the eternal unity of the Church in Christ can really be broken, is akin to believing that human courts can undo the work of God in a valid sacramental marriage. The Church's various divorces, whether in 1054 or in the 16th century, do not annul its unity in Christ; for if it did, members would be cut off and die simply because of human failing. Where true faith is present, we are in Christ; and, unless one can rob a Christian of his faith, he cannot cut him off from Christ (Romans 4:16).
Our unity is both a present and eternal fact, because we are in Christ. We should make efforts to understand each other, to be very clear in communication, to work for the resolution of theological and political separation, and to cultivate charity by the grace of the Holy Spirit who is within us all. But, we must not let this become mere sentimentality, and neither must we feel anxiety or pressure to leap forward faster than honest and clear communication allow. We already are one in Christ, and can proceed toward a resolution of differences in polity only with theological clarity and respect for everyone's conscience.