Reading the second edition of Richard Bauckham's Jesus and the Eyewitnesses today, I came across an interesting suggestion. Building upon the idea that the "John" of the Gospel of John was a Jerusalem-based follower of Jesus (and that he is also the Beloved Disciple who features in the gospel), Bauckham suggested that the book's distinctive character might stem from its ultimate origin among a different "circle" of eyewitnesses than the Synoptic Gospels. I was already quite convinced that Johannine distinctiveness was largely a consequence of an author who was a disciple of the earthly Jesus was Jerusalem-based but not one of the Twelve, but the idea that he was a representative voice of a circle of eyewitnesses outside the Twelve had not occurred to me. It is is not without certain attractions.
One such attraction: this hypothesis makes good sense of the Johannine "we-passages." These passages talk in the first-person plural about having witnessed Jesus' glory (1:14b) and knowing that the author's testimony was true (21:24). When I reflect upon these passages in light of Bauckham's suggestion, it occurs to me that they are most naturally read as indicating that at least three eyewitnesses were involved in the development of John's Gospel: John, the Beloved Disciple, the two or more who know his testimony is true in 21:24, and all three or more of these who claim to have witnessed Jesus' glory in 1:14b. As I think about it, I suspect an implicit claim to eyewitness status in 21:24 because the gospel generally links knowing and seeing. For John, to know is to have seen, and if one knows that something is true that is typically because one has seen it. With regard to 21:24, this would only be true of those who had seen the things to which John testifies.
Another attraction: we actually do know of at least two distinct groups of Christians present in Jerusalem during the first year or two after Jesus' life, namely the Hebraioi and the Hellēnistai, the Hebraists and the Hellenists. It doesn't seem that they lived separate institutional lives, but the early Christians were cognizant that there were distinctions between them. While the majority of Jesus' Galilean followers were likely among the Hebraists, it is not unreasonable to expect that at least some of his Jerusalem-based followers were among the Hellenists. It strikes me as hardly inconceivable that the distinctions between Hebraist and Hellenist might not in part have been the grounds for the literary distinctions that we find in the Synoptic and Johannine traditions. Of course, it doesn't follow that either tradition closely resembled their written form at this point, but the idea that the developments that led to those written forms should be located in this first year or two should perhaps not be ruled out.
Interestingly, the above hypotheses (which is all they are: untested hypotheses) would have the consequence of grounding early Christian diversity at least in part in the pre-Easter period. Distinctions between Synoptic and Johannine traditions that can be seen clearly decades after Jesus' death could be in part the consequences of his operations. Put otherwise, following the traditional Lukan narrative that sees Christianity as initially expanding from a relatively small group Jerusalem does not require one to assume that Christianity was homogeneous. It was in principle as diverse as the people who joined Christianity during this period.