"Paul combines in himself both ascribed and voluntary elements of identity, as he things of himself as someone who was born a Jew but no longer considers himself one. That he privileges the voluntary without dismissing the ascribed is apparent from the way that he divides people into three distinct groups - Gentiles, Jews, and believers - while maintaining that the latter two collectives form separate groups of descendants from Abraham (Rom. 4.11-12, 16). Thus, in one sense Paul was both Jewish and Christian given that he was born Jewish and later chose to identify with Christ; but in another sense he was a former Jew, because he did not hold to both of those identities with equal loyalty when he considered the arc of his personal narrative (Phil. 3.3-11)." - Love Sechrest, A Former Jew: Paul and the Dialectics of Race (LNTS 410; London: T&T Clark, 2009), 159.It's a really interesting argument, one that addresses a clear puzzle in Paul. I especially like her distinction between insider (voluntary) and outsider (ascribed) perspectives on group identity. I look forward to reading the whole thing carefully when I can drum up some time, and either $90 or a review copy--preferably the latter.
Update: I should note Joel Willitts's helpful critical response. Willitts thinks Sechrest "too boldly draws lines between the categories of Religion, Geography and Customs, Lifestyles and Laws", which may well be correct; I will have to check. In response to Joel's second complaint--that "Sechrest engages a narrow swath of scholarly literature"--it's worth observing that she engages helpfully with a wide "swath" of scholarship on race and ethnicity, and her choice of Daniel Boyarin and Caroline Johnson Hodge as conversation partners in the conclusion seems entirely appropriate.