Paul N. Anderson in The Riddles of the Fourth Gospel does not like how the search for the historical Jesus has proceeded by programatically discounting the evidence from the Gospel of John. This is wrong because the John has a realism and empiricism that gives it historical credibility.
It has a realism in that it seems genuinely aware of the situation in Judea in the early first century. It has a religious realism in that it is aware of actual feelings about such things as the Temple and the Samaritans. It has a political realism because it is aware of the players. For instance, it gives a place to Annas, the former high priest who was still the power behind the high priesthood. This realism is reinforced by several occasions where archeology has shown that John accurately describes features of Jerusalem at that time.
John has an empiricism in that it stresses what witnesses have seen and heard. Anderson thinks it is likely that John the Apostle is the witness referred to at the very end of the gospel who “is testifying to these things and has written them” (John 21:24).
In Anderson’s understanding this concludes the second edition of John. The second edition comes from John the Elder and refers back to the first edition which was either written or caused to be written by the late apostle, John. This does not mean that John is the eye-witness to everything in the gospel. There may be others. For instance, 19:35 refers to a witness to the piercing of Jesus’ side who may or may not have been the author.
The objection has been that John is not credible because it is theological and this emphasis on theology distorts its historical reliability. But all the gospels are theological.
A case in point is the difference about when the Last Supper occurred. Mark, followed by Luke and Matthew, make it a Passover meal. But they may have done this for theological reasons to point to Christ’s death as a sacrifice. John also believes this and calls Jesus the Lamb of God (1:29). However, he corrects the chronology of the synoptics by putting the meal “before the Passover” (13:1) and putting the crucifixion on “the day of preparation” (19:31). John’s version has much to commend it historically. So this seems like a case where the other gospels have let theology come before history.
Also, I already was convinced that the most likely historical scenario is that Jesus attended several festivals in Jerusalem which the other gospels compact down into a single visit. So I think the incident about the money changers in the temple courts happened at an earlier festival. Anderson believes this also.
The synoptic gospels have Jesus’ ministry starting after the arrest of John the Baptist. John has the ministry of Jesus and John the Baptist overlapping. Anderson thinks that we should consider that it is more likely that John is historically correct about this.
John seems to have a more detailed and knowledgeable account of the trial and crucifixion events
Anderson calls the disregarding of John in historical Jesus studies the “de-Johannification of Jesus”. If we re-Johannify Jesus we get not an anti-establishment cynic, a marginal wisdom teacher, or an apocalyptic prophet but what Anderson calls a “revelatory prophet”. Jesus is the prophet like Moses who reveals God’s love for the world and seeks to embody it. This may come close to how Jesus saw himself. So Anderson wants a fourth search for the historical Jesus that takes the Jesus of John’s gospel more seriously.
Anderson does not deal much with what I think is the big hang up of the Jesus Seminar and other historical Jesus scholars. That is that the beloved disciple also is an eye-witness to the empty tomb (John 20:4-9). This is a challenge to their world-view. They tend to see all the witness claims of John through their disbelief in that one.
As for how the story of Jesus would look if we considered John more of a historical work, C. H. Dodd decades ago wrote a popular book like that. And it is now available free online here. The book: The Founder of Christianity.