Philip

[John2]

And I see that Dunn goes on to list three options for why Paul persecuted Christians, with the third one (on page 340) being similar to what I'm thinking.

He saw the first Christians as abusing and abandoning the law, the very centre of his religion as a scrupulous Pharisee, and therefore as threatening Judaism itself. This would fit with his own description of his previous self as 'exceedingly zealous for my ancestral traditions' (Gal. 1:14).

I'm thinking that by "law" and "my ancestral traditions" Dunn may mean the written Torah, and if so, it would not make sense to me since Jesus and (Jewish) Christians (to judge from Paul, Mark, Acts, and Jewish Christian writings) were observant of the written Torah. So I think Paul, as a Pharisee, and in keeping with his use of the expression "traditions of my fathers" (which typically refers to the oral Torah) and the evidence that Christians were written Torah observant, would have rather been offended that Christians rejected the oral Torah.

[John2]

Without the oral Torah, Fourth Philosophers (like later Karaites, who emerged from Rabbinic Judaism) inevitably had to have "innovations" (as Josephus calls them), or a "new covenant" (as the NT and the Damascus Document call it), which is why I think Mk. 1:22-27 says of Jesus:

And they were astonished at his teaching, for he taught them as one who had authority, and not as the scribes ... And they were all amazed, so that they questioned among themselves, saying, “What is this? A new teaching with authority!"