John’s thought is so wonderfully integrated that attempts to compartmentalize it by itemizing its components are destined in some measure to misrepresent it. The best theological summaries are provided by Barrett and Schnackenburg. Among John’s more important contributions are the following:
1. John adds stereoscopic depth to the picture we might gain of Jesus and his ministry, death, and resurrection from the synoptic accounts alone. By telling the same story from another angle, with many things omitted that they include and with many emphases that they scarcely treat, the total portrait is vastly richer than what would otherwise have been achieved.
2. John’s presentation of who Jesus is lies at the heart of all that is distinctive in this gospel. It is not just a question of the shading assigned to certain Christological titles— whether those found only in the fourth of the gospels (e.g., Lamb of God, Word, I Am), or those found in all four (e.g., Son of Man, Christ, King). Rather, fundamental to all else that is said of him, Jesus is peculiarly the Son of God, or simply the Son. Although “Son of God” can serve as a rough synonym for “Messiah,” it is enriched by the unique manner in which Jesus as God’s Son relates to his Father: he is functionally subordinate to him and does and says only those things the Father gives him to do and say, but he does everything that the Father does, since the Father shows him everything that he himself does (5:19ff.). The perfection of Jesus’ obedience and the unqualified nature of his dependence thereby become the loci in which Jesus discloses nothing less than the words and deeds of God.
3. Despite the heavy emphasis on Jesus as the one who reveals his Father, salvation does not come (as in Gnosticism) merely by revelation. John’s work is a gospel: all the movement of the plot is toward the cross and the resurrection. The cross is not merely a revelatory moment: 103 it is the death of the shepherd for his sheep (John 10), the sacrifice of one man for his nation (John 11), the life that is given for the world (John 6), the victory of the Lamb of God (John 1), the triumph of the obedient Son, who in consequence bequeaths his life, his peace, his joy, his Spirit (John 14-16).
4. John’s distinctive emphasis on eschatology is bound up with his use of the “hour” theme (often rendered “time” in the NIV: e.g., John 2:4; 7:6). All the major New Testament corpora display the tension of trying simultaneously (1) to express the wonderful truth that in the ministry, death, resurrection, and exaltation of Jesus, God’s promised “last days” have already arrived, and (2) to insist that the fullness of hope is still to come. Different authors set out the tension in different ways. In John, the hour “is coming and has now come” (4:23; 5:25); Jesus has bequeathed his peace, but in this world we will have trouble (16:33). Above all, in the wake of Jesus’ exaltation and his gift of the Spirit, we can possess eternal life even now: that is characteristic of John, who tilts his emphasis to the present enjoyment of eschatological blessings. But this is never at the expense of all future hope: the time is coming when those who are in the graves will come out to face the judgment of the One to whom all judgment has been entrusted by the Father (5:28-30). If John asserts that Jesus even now makes himself present among his followers in the person of his Spirit (14:23), he also insists that Jesus himself is coming back to gather his own to the dwelling he has prepared for them (14:1-3).
5. Although John’s teaching on the Holy Spirit has important similarities to synoptic emphases (e.g., cf. John 3:34 and Luke 4:14-21), there are numerous strands that are unique. Jesus not only bears and bestows the Spirit, but by bequeathing the eschatological Spirit, he discharges his role as the one who introduces what is characteristic under the new covenant (3:5; 7:37-39). In the farewell discourse (John 14-16), the Spirit, the Counselor, is clearly given in consequence of Jesus’ death and exaltation. The elements of what came to be called the doctrine of the Trinity find their clearest articulation, within the New Testament, in the gospel of John.
6. Although John does not cite the Old Testament as frequently as, say, Matthew, his use of the Old Testament is characterized by an extraordinary number of allusions, and above all by his insistence that Jesus in certain respects replaces revered figures and institutions from the old covenant (e.g. temple, vine, tabernacle, serpent, passover). The underlying hermeneutic assumed deserves close study.
7. No gospel better preserves the ways in which Jesus was misunderstood by his contemporaries, including his own followers. This feature not only provides an entrance into various historical questions, as we have seen, but is itself a reflection on the relation between the old covenant and the new. For the same gospel that insists that Jesus fulfills and in certain respects replaces many Old Testament features equally insists that most of these points were not grasped by Jesus’ disciples until after his exaltation.
8. Not a little attention is devoted to what it means to belong to the people of God. Although there is nothing on church order per se, there is much on the election, life, origin, nature, witness, suffering, fruit-bearing, prayer, love, and unity of the people of God.
9. We have seen that John in certain respects provides greater depth than do the Synoptic Gospels, but on relatively restricted topics. That is a major reason why his vocabulary is relatively small, with certain words and expressions occurring again and again. This repetition becomes an index of some of the things that are important to him. For instance, he uses the verb “to believe” 98 times; the “love” words 57 times; “world” 78 times, the “to send” verbs 60 times, “Father” 137 times (mostly with reference to God). However tricky it is to approach an author’s theology through word studies, in John’s case such studies constitute an important entrée.
10. The complexities that bind together election, faith, and the function of signs are repeatedly explored. If faith bursts forth in consequence of what is revealed in the signs, well and good: signs legitimately serve as a basis for faith (e.g., John 10:38). In contrast, people are excoriated for their dependence on signs (4:48). It is a better faith that hears and believes rather than sees and believes (20:29). But in the last analysis, faith turns on sovereign election by the Son (15:16), on being part of the gift from the Father to the Son (6:37-44). This truth is at the heart of a book that is persistently evangelistic.