The problem of Jewish ethnocentrism according to the New Perspective on Paul

Timothy Gombis's new book and excellent CT article on Paul seems to have stimulated a spate of positive posts on the "New Perspective on Paul" by evangelical bloggers. The "New Perspective" has taken on an ill-defined life of its own, but it originally referred to a reading of Paul from the fresh vantage point of a new understanding of Judaism instead of from the long tradition of Christian interpretation that--as John Barclay explains it--treated the Jews "in Paul's letters as symbols of something else, normally some negative trait in the human condition." For the sake of comparison, here are some prominent representatives of the old perspective:

• Augustine: The Jews had a boasting problem. They were guilty of "the most fundamental human sin, the sin of self-reliance (an introverted idolatry)."
• Luther: The Jews had a self-righteousness problem. "Luther took Paul's reaction to Judaism to be an assault on all forms of self-righteousness, which by 'doing' seek to make a claim on God and thus refuse his sheer grace in Jesus Christ."
• F.C. Baur: The Jews had a particularity problem. "Paul stands for the 'universal' and the spiritual, as opposed to Judaism with its 'narrow' ethnic base and national 'particularity.'"
• Käsemann: The Jews had a piety problem. "Paul is taken to criticize, via Judaism, the piety and self-conceit of 'the religious man': it is such piety that leads to pride in privilege or achievement, and where Paul discusses this problematic, according to Käsemann, he is attacking 'the hidden Jew in all of us.'"

(All quotations are from John M. G. Barclay's excellent essay, “Paul, Judaism, and the Jewish People,” in The Blackwell Companion to Paul [Stephen Westerholm, ed.; United Kingdom: Wiley-Blackwell, 2011], 188-201, here 190.)

I am very sympathetic to those who want a perspective for reading Paul that treats Judaism fairly. Perhaps I am prone to over-correction in this regard, since I find myself reacting to one common "New Perspective" construal of what Paul found wrong with Judaism. Consider the following examples:

• First, Timothy Gombis's CT article: "First-century Judaism didn't have a legalism problem; it had an ethnocentrism problem. The first followers of Jesus were all Jewish, and had difficulty imagining that the God of Israel who sent Jesus Christ as their Savior could possibly save non-Jews without requiring them to convert to Judaism." (Also quoted and affirmed by Scot McKnight.)
• Daniel Kirk, summarizing Gombis: "First, he challenges the common perception that at his conversion Paul left behind a legalistic Judaism in favor of a salvation-by-grace Christianity. This is a nice, short summary introduction to the New Perspective: Paul’s problem with Judaism wasn’t legalism, but ethnocentrism. But Paul himself remained a Jew and never called other Jews to leave their Judaism behind." 
• Michael Bird: "What have we learned from the New Perspective, what gains are we to keep? ...2. The problem of Jewish ethnocentrism. What Paul opposed in Galatians was the view that one has to become a Jew in order to be a follower of Jesus. Instead, Paul argued that God saves Gentiles as Gentiles through the Lord Jesus. This is all the more pertinent if we map Paul onto an increasingly aggressive anti-Gentile sentiment in Judea in the 40s and 50s. That is why the logical opposite of justification by faith without works of law is the notion that God is the God of the Jews only (Rom 3:29). Paul effectively dissolves the categories of proselytes and God-fearers for Gentiles and makes them equal with Jews in the new covenant." In a follow-up post, Mike adds that "Paul’s problem with Judaism was not merely exclusivism ...", but ethnocentrism apparently still remains a problem.

It is curious that new perspective scholars in the Dunn / Wright tradition still create a negative picture of Judaism as a foil for early Christianity. It may just be me, but the sins Augustine and Luther identify seem more fundamental to the human condition than 'ethnocentrism'. The ideas preach better, and with greater power because they are centred in a big view of God (and in deep elements in Paul's thought) rather than on an admittedly grievous social ill. So if we have to stereotype Judaism, I'll take Augustine and Luther, thank you very much.

But of course, we can try not to stereotype ancient Judaism--which leads me to my next point: What was wrong with Jewish ethnocentrism? What is wrong about the people of God thinking they are the people of God? Isn't that what the Old Testament encourages? Was it even conceivable to think that Israel would be a light to the nations without being distinctive as a people? Would anyone have imagined that God would save all the nations of the earth without their joining the covenant of the people of God? And does Paul ever criticize non-believing Jews for being ethnocentric? (What am I missing?)

Finally, was early Christianity any different? Sure Gentiles were not required to become Jews, but they were required to join 'the people of God'. I submit that first century Judaism was not any more "ethnocentric" than normative Christianity is.