For one, verse 23 ends with what appears to be the climactic and therefore defining clarification. Jesus prays that the “perfected unity” of his left-behind community would “let the world know that you sent me, and have loved them, even as you have loved me.”
Here the oneness of Father and Son is the love the Father has for Jesus. The Father’s love for the Son shows up again in v. 24b, where Jesus says that Father has loved him “before the creation of the world.”
Finally, at the end of his prayer, Jesus’ prayer for his disciples is that the “love you have for me may be in them” (v. 26). Jesus asks that the love the Father “had” for the Son may be “in” the church.
It is precisely the divine inter-trinitarian love between Father and Son that Jesus asks be present within the community of disciples. This inter-personal love between the Father and the Son is the paradigmatic “oneness” that the church must participate in and manifest to the world in their own community. Schnackenburg explains, “The unity that is desired is brought about in reciprocal love" (R. Schnackenburg, The Gospel According to John, vol. 3 (London: Burns & Oates, 1982), p. 303.)
Because of its compact formulations, John 17:20-23 invites the reader to explore just how the Father and Son are one by re-reading the Gospel with a view toward discerning the manner in which the loving relations between Father and Son serve as a model for the project of unification that must be “seen” in order that the world will believe.
That a oneness grounded in love for one another is indeed Jesus’ concern in John 17 finds support in John’s epistles. There John uses the same sort of “perichoretic” language to refer to our participation in and imitation of God’s love. “God is love. Whoever lives in love lives in God, and God in him” (1 John 4:16b).
Note: See Gruenler’s The Trinity in the Gospel of John, for a thorough investigation into the inter-trinitarian personal relations as they are revealed in the interaction between Father, Son, and Spirit in the Fourth Gospel. Even though the Gospel of John was a major source for the patristic doctrine of the Trinity, they never seem to have mined it for its implications for human sociality (see Cornelius Plantinga Jr., “The Fourth Gospel as Trinitarian Source Then and Now,” in Christian Faith and Practice in the Modern World: Theology From an Evangelical Point of View, ed. By Mark A. Noll and David F. Wells [Eerdmans, 1988], pp. 303-321). Augustine, for example, seems so bent on illustrating the ontological unity of the Three that he disparages their social or interpersonal unity. Although he mentions it in passing, he does not linger over it. Jean-Baptiste Du Roy argues that Augustine was enough of a Christian churchman in submission to the written Word to be attracted to ecclesiastical intersubjectivity from John 17 as a viable social analogy for the Trinity, but too beholden to Neoplatonic ontology to fully embrace it (“L’expérience de l’amour et l’intelligence de la foi trinitaire selon saint Aubusin,” Récherches augustiniennes 2 : 441-43).Continue Reading Part XII