The Gospel of John is something of an enigma. Scholars believe it was probably written by a community of writers in conversation with the compilers of 1-3 John and Revelation. The text’s cohesive theological structure and good-but-not-great Greek grammatical construction point to a late-first or early-second century authorship date, making it perhaps the latest of the four surviving gospels.
Clement of Alexandria (150-215 CE) once famously described John as “the spiritual gospel.” This observation reflects the work’s apologetic emphasis on the cosmic, theological importance of discourses and ideas rather than a more straightforward, chronological recording of natural (and supernatural) events.
The Gospel of John is clearly divided into four parts. The first 18 verses comprise a theological and philosophical Prologue that confirm Christ’s oneness with God as the embodied Word (Gr., Logos) of God preexistent to creation. Chapters 2-12, sometimes referred to as the “Book of Signs,” describe Christ’s earthly ministry, centering on a series of seven “I Am” statements affirming Christ’s messianic identity and mission. Chapters 13-20 make up the “Book of Glory” and relate the Passion narrative; in fact, nearly ¼ of the entire gospel takes place at the Last Supper.
Chapter 14 appears in the middle of Christ’s Final Discourse, which represents both a sort of Q & A session with his closest followers and a promise of further revelations to come. Even as Christ explains (again) to his disciples that he is one with the Father, and that together they will send another Comforter and Advocate (Gr., Paraclete) to further reveal the truth, Judas the son of James insists, “Lord, how is it that you will reveal yourself to us and not to the world?” Our text begins with Christ’s answer to this important question.
“Jesus answered him, ‘Those who love me will keep my word, and my Father will love them, and we will come to them and make our home with them.’”
The Greek word emphanizien, translated here as “reveal,” is the same one used in Greek translations of the Old Testament to describe Moses’s theophany on Mt. Sinai. Like his fellow disciples, Judas (called Jude in some English translations) seems to anticipate a supernatural show of divine power. Instead, Christ promises to reveal his oneness with God by building a new kind of community amongst his loving followers.
The Greek root word mone, translated here as “home,” echoes Christ’s earlier reassurance to his disciples: “In my Father’s house there are many dwelling places. If it were not so, would I have told you that I go to prepare a place for you?” Thus, the promise of the Holy Spirit points to a realized, holistic eschatology of love and mutuality: the beloved community to come has already begun in the here and now. “Whoever does not love me does not keep my words; and the word that you hear is not mine, but is from the Father who sent me.”
For Jesus, the meaning of discipleship is clear: to follow his example is to faithfully embody God’s love for all of creation. This loving obedience—empowered, enabled, and encouraged by the Holy Spirit—is the only option for followers of Christ. And in the same way that the Father sent the Son, and together they will send the Spirit, the disciples too will be sent into the world to embody a gospel of love. “I have said these things to you while I am still with you. But the Advocate, the Holy Spirit, whom the Father will send in my name, will teach you everything, and remind you of all that I have said to you.”
John’s trinitarian theology is unmistakable: Christ and the Father are One; Christ and the Father are Love; and Christ and the Father will send the Spirit together. The Advocate’s transformative role is similarly clear: the Spirit will not only comfort the believers, but also remind them of Christ’s loving instruction and example. This reassurance and reinterpretation must have been vital for disciples who so frequently misunderstood their teacher’s intentions and objectives!
“Peace I leave with you; my peace I give to you. I do not give to you as the world gives. Do not let your hearts be troubled, and do not let them be afraid.”
The peace (Gr. eirenen; Heb. shalom) Christ speaks of here is not about merely defeating enemies or even the cessation of hostilities. It’s certainly nothing like the Pax Romana of occupied first-century Palestine, which depended on brutally suppressing any opposition. This otherworldly peace—promised even as Christ must have known the likelihood of his own arrest, torture, and execution at the hands of religious and political collaborators—is rooted in a deep, unshakeable confidence that love is bigger than hate and life is stronger than death. Chapter 14 concludes as it begins: with Christ encouraging his confused and frightened disciples. “Do not let your hearts be troubled,” he repeats before adding, “and do not let them be afraid.” In doing so he affirms one of most frequently repeated promises in all of scripture, from Abraham and Moses to Israelite prophets and Judean shepherds: “I am with you. Do not be afraid.”
Johannine literature further develops this idea in 1 John 4:18. “There is no fear in love, but perfect love casts out fear; for fear has to do with punishment, and whoever fears has not reached perfection in love.” Here again we see John’s trinitarian claims on full display: Christ and the Father are One; Christ and Father are Love; and Christ and the Father will send the Spirit to encourage and empower the faithful.
You heard me say to you, 'I am going away, and I am coming to you.' If you loved me, you would rejoice that I am going to the Father, because the Father is greater than I.
Orthodox Christian trinitarian theology developed over the course of more than three hundred years (incorporating aspects of Hebrew monotheism, Hellenic philosophy, Egyptian tritheism, and Messianic Judeo-Christianity). Yet despite John’s sometime seeming subordination of the Son to the Father, the gospel’s early, high Christology is clear: not only does Jesus represent the primary, earthly embodiment of God’s love for all of creation, but his unity with the Father in sending another, subsequent Advocate also affirms the trinitarian claims of Johannine literature. “And now I have told you this before it occurs, so that when it does occur, you may believe.”
As perhaps befits a later work, John’s gospel tends toward the reflective. The authors sometimes lend their own perspectives to the text, occasionally obscuring which thoughts and phrases are character’s original insights and which are later interpretive additions. Nowhere is this phenomenon more striking than the “so that you may believe” statements found in Chapters 14 and 20. However, both instances affirm the central thesis and purpose of the Gospel of John. The former is that Jesus and the Father are One; Jesus and the Father are Love; and Jesus and the Father will send the Spirit to equip, empower, and encourage believers to continue the love-filled, life-giving work of Christian discipleship. And the latter is that this gospel—this cosmic, spiritual, trinitarian gospel—was written so that we might believe.
Thanks be to God!
 Chapter 21 represents a brief, somewhat controversially included Conclusion  Confirmed in John 15 and elsewhere; there was an entire Filioque Controversy about this.  The former is more neatly and narratively integrated than the latter.