I'm continuing my way through Alan Segal's Paul the Convert. A few things stood out to me.
First, I have long wondered: If many Jews believed that Gentiles could become righteous and enter the World to Come without becoming Israelites and keeping the entire Torah----and, if my impression is correct, Segal does appear to believe that there were many Jews who believed this way, on the basis of references to God-fearers on inscriptions and in literature----then why was Paul so revolutionary and provoking towards Jews when he said that Gentiles did not have to be circumcised in order to be saved? And why did many Jews believe that being part of Israel was such an honor, if they did not even think that one had to be an Israelite in order to be saved?
On pages 194-195, Segal tackles this question. Segal says that, according to Pharisaism, being a part of Israel was a special honor, like the priesthood. One did not have to be a priest to be righteous, but being a priest was an honor. And with the honor of being a part of Israel (and being a priest, for that matter) came purity rules. According to Segal, purity rules separated Jews from Gentiles and hindered social interaction between them (particularly sharing a meal). But Paul was coming along and saying that Jews and Gentiles could join together into a holy community and could interact with each other----even going so far as to share meals together. That, for Pharisaic Judaism, was quite radical.
Second, Segal offers a unique (as far as I can see) perspective on Romans 7, in which Paul appears to struggle with his sinful nature. According to Segal, Paul is actually struggling against something else in this chapter: his desire to keep the Torah. For Segal, Paul believes that Gentiles do not have to be circumcised and keep the ritual laws of the Torah in order to be a part of God's people, and Paul probably doesn't think that Jews have to do those things, either, for he, as a Jew, does not feel bound by them. But Paul did make accommodations for the sake of church unity or to be tactful, as when he had Timothy circumcised because Timothy had a Jewish mother. (Against those who note that Judaism at this time believed in patrilineal rather than matrilineal descent, Segal says that Acts may be getting things wrong, and also that Judaism may be more diverse on this issue than we think.) For Segal, Paul in Romans 7 is planning to tolerate the observance of Jewish dietary laws among Christians, and even perhaps to keep them himself when he feels that the situation calls for that, but he is afraid that this will make him one who relies on the flesh rather than the Spirit. He notes that he has a desire to keep God's law, and so he fears that observing some Jewish rituals will draw him back into the Jewish religion, or a Jewish-Christianity that he believes promotes confidence in fleshly observances rather than the Spirit. In the end, for Segal, Paul resolves to tolerate Jewish-Christian practice when necessary, while remembering that faith is what is important.