"The Gospel of John is anonymous; no name appears to explicitly introduce us to its author. Yet several clues are given throughout the Gospel, which help solve the mystery. One of those clues is the fact that a certain disciple is regularly referred to as, 'that disciple whom Jesus loved'. For example, in John 13:23–24, we read that this disciple whom Jesus loved was seated next to the Lord during the Last Supper. We know from reading the Gospel accounts that three disciples were closest to the Lord: Peter, James, and John. Since James had already died before the Gospel was written (85–95 C.E.), that left only Peter and John as possible authors. Another clue to the mystery author is found in John 19:26, where we read that the disciple whom Jesus loved was standing with Mary at the cross. Peter had fled earlier in the night, weeping because of his betrayal and guilt. Only John remained.
"The final clue is found in the last few verses of the Gospel. Peter was walking and talking with the resurrected Lord and during their conversation Peter, 'saw the disciple whom Jesus loved following them' (John 21:20). Following Peter's conversation with Christ, that same disciple who was following Peter and Jesus wrote, 'This is the disciple who bears witness of these things, and wrote these things...' (John 21:24).
"While John never referred to himself directly, there is no question that this beloved disciple wrote the grandest account of Christ's biography in the whole world.
"John's purpose for writing the Gospel is very clear. 'Many other signs therefore Jesus also performed in the presence of the disciples, which are not written in this book; but these have been written that you may believe that Jesus is the Christ, the Son of God; and that believing you may have life in his name.' (John 20:30, 31)." 
The text quoted in the paragraph above emphasises salvation through belief, and the same idea occurs in the much-quoted John 3:16. John's is sometimes described as an intellectual Gospel, more attuned to Greek thinking than Jewish ideas. One might call it the first international version! However, one does not have to have deep understanding to understand John; he concentrates on hard evidence and practical service (see comments on the First Epistle of John). John frequently refers to witnesses[2 p.11]. After placing Jesus in a timeless context in the opening verses of chapter 1, he puts him in a historical context by reference to John the Baptist. It appears that he assumes that his readers have heard of John. This focus on the tangible physical evidence was unusual in an age that emphasized spiritual things. All five senses are mentioned:
This book has always been linked with someone called John[31 p.74], and "John's Gospel is part of a 'school' of writings which include the three Epistles and Revelation" [2 p.154]. The book was probable written in the last quarter of the first century, probable in the last decade. The author probably knew at least one, perhaps all, of the other three canonical gospels, as well as aural tradition.[2 p.101].
This Gospel has traditionally been associated with an all-seeing eagle (one of the four living creatures in Ezekiel 1:4–28 and Revelation chapters 4–6) who was present with God in the creation, took flesh in the incarnation, gathered his disciples under his wings, before ascending to his Father in his risen power [47 p.7].
John's Gospel has a distinct style throughout, indicating that it had a single author.[31 p.89] A later editor would have removed difficulties such as 14:31b.[31 p.107] The author was able to instruct the churches because he embodied Christian tradition, and was well known, so no name need be mentioned.[31 p.29]
John frequently uses the term the Jews in a derogatory sense, and in the third person, suggesting that the intended audience was gentile Christians and excluded Jewish converts.[31 p.118–9] He means those Jews who reject Jesus, which may be the authorities in Jerusalem or crowds demanding signs in Galilee[2 p.29]. He portrays Christianity as being what Judaism claims to be, and consequently his theology is grounded in Exodus and Deuteronomy[2 p.166].
The Gospel is precise concerning the geography and customs of Palestine, Judaea and Samaria. In John's Gospel hardly anything of consequence happens in Galilee, unlike the Synoptics. That points to an author who was not a Galilean fisherman as John son of Zebedee was. The Roman authorities only banished upper-class and influential people to remote islands like Patmos. Also John's Gospel shows excellent knowledge of Jerusalem and Judaea. Also it is less focussed than the Synoptics on the problems of the poor. Hengel concludes that the author of John's Gospel was not John son of Zebedee but a man from the Jerusalem upper class, known to the high priestly families, who witnessed Jesus's ministry and death in his late teens.[31 p.111, 124, 126, 130]
There are curious differences between John and the Synoptic Gospels (see Gospels); he places the Great Confession on the lips of Mary sister of Lazarus (John 11:27) rather than Peter; he gives greater prominince to women that the synoptics, such as most of Chapter 4 being focussed on the woman at the well. Another significant difference is that he replaces the institution of the Eucharist with foot-washing. The meaning of the Eucharist is there nonetheless, in verses like John 6:32–35 and 6:48–58. John validates Jesus's ministry by miracles, rather than as fulfilment of prophecy as in the synoptics. John, the only disciple to witness the crucifixion, presents it not as martyrdom but revelation, giving a different emphasis to his entire Gospel.
The book is written more as drama than dogma or assertions, and so conveys richer meaning. Rather than telling us what to believe, it generally (the prologue being an exception) challenges us to ponder how the events of Jesus's life apply to our own context, often using the sequence "as... so..." By describing foot-washing in place of holy communion he makes the application of Jesus's example open to all believers rather than just the clergy.
There are allusions to the Hebrew scriptures, rather than the specific quotations in the synoptic Gospels. The glory and power of God is shown in many references to bounty. Jesus brings the limitless glory and power of God to all people without discrimination or limit; that is the Christian Gospel that we should demonstrate and proclaim, the light that should shine in darkness everywhere. (cf. Isaiah 9:2.)
The Greek in the Revelation to John is poor, but that in John's Gospel is good, so many commentators suppose he must have worked on it with others. Nevertheless, both the Gospel of John and the Apocalypse are written in Greek with a strong Hebrew influence.[31 p.110] The teaching style favours sequences of three incidents or statements which build to a climax, such as John 1:1, and groups of "truly, truly" sayings.
John selected seven "signs" that clearly proved the deity of Christ and his rightful claim as Messiah. (The word used for "sign" is the one used in legal proceedings for a proof.) In them he met and exceeded needs of every kind, each time with commanding words echoing John 1:1:
There are also seven occasions when Jesus says "I am..." echoing the name of God: (Exodus 3:14, Isaiah 41:4 and 43:11). These replace the "dominical words" at the institution of the Lord's Supper in the Synoptic Gospels.
The book is structured as follows:
Jesus is the light of the world, revealing God's love. By accepting him, and thus his message, people become born to spiritual life, and destined for eternal life in heaven. Jesus is the good shepherd of his people, who gives up his life for them. We should respond by "washing each other's feet" and the disciples are to "feed my lambs".
It is curious that John does not include any of the parables and stories Jesus told, nor the institution of baptism or holy communion (but see 6:54). Perhaps John omits holy communion because he sees the statement "I am the bread of life" as far too far-reaching to be summed up in a single ritual; Jesus is supposed to energise our entire lives.
It is sometimes claimed that John's Last Supper discourse (John 13:31–17:26) is too long to have been said on one occasion, and must be concocted from a number of sayings. In fact it amounts to just under 3,000 words, and could have been delivered at 100 words per minute in half an hour.
© David Billin 2002–2021