In this post, I would like to bring forward another forgotten criterion in the search for the historical Jesus, the view common to friend and foe. I have looked through several discussions of criteria in historical Jesus research and have not found, yet, a single reference to this criterion, let alone any engagement with it. More is the shame, because here we are on solid ground.
E. P. Sanders and Margaret Davies, Studying the Synoptic Gospels (London: SCM; Philadelphia: Trinity Press International, 1989):
At first it seems that all the evidence is biased towards jesus. It is, however, extremely important to note that, while we have for Jesus no equivalent to Aristophanes on Socrates, we can discern in the gospels that he offended many and that he was executed on a serious charge. That is, the gospels, though biased in his favour, give us a glimpse of the views held by those who were biased against him.
Once we can discern both favourable and unfavourable portraits of Jesus, we can ask what is common to both portraits and we may have considerable confidence that what is common is historically sound . . . (302).
. . . .The gospels are based on 'propaganda', bias (in this case, in a good cause). We would understand more about Jesus and his impact -- or lack of it -- if we knew what his enemies thought. What friend and foe agreed on is presumably reliable material. Two facets of his career and message stand out as proved on this basis.
1. Miracles. In Jesus the Magician Morton Smith pointed out that we possess the enemies' view of Jesus as a miracle-worker. He was a magician. He could, they granted, cast out demons, but he did so by invoking Beelzebul . . . . (330)
This discussion gets ignored, I would guess, for the same reason that many others of the gems in Studying the Synoptic Gospels get missed (e.g. the best discussion of form-criticism available anywhere, brilliant discussion of the Synoptic Problem). For some reason that I have never been able to fathom, scholars do not seem to read this book. Sanders's second example of this criterion (or "test", as he calls it) is the king / kingdom material, and I am less sure of the historicity of the kingship material in Mark's Passion Narrative than Sanders is, and I don't want to take away from the discussion of a strong criterion by bringing in a less certain example. But I would want to add other elements in the tradition that this criterion helps us with, on which more anon.
Update (Sunday, 17.55): Gary Greenberg emails: "I think this criterion needs stronger controls. The example cited doesn't really show that the foes had the view attributed to them. It is a polemic written long after the event by someone who was not a witness and it may be an invention or misrepresentation of what was said. What I suggest may be more useful is where a view is attributed to a foe contemporaneous with the author, say as in the disputes mentioned in Paul's letters between Paul and the Jerusalem Church or factional disputes in the Churches founded by Paul. While not a perfect control, it seems to exert more pressure on the author to come closer to what the opponent says than if he were writing about someone who wasn't around to respond."
See also the comments. I will comment on these points when I next have a moment.