I started Stephen Westerholm's Perspectives Old and New on Paul: The "Lutheran" Paul and His Critics. I have two items for today.
1. In his "Whimsical Introduction", Westerholm constructs a scenario in which he and a friend meet Martin Luther at a bookstore and show him scholarship on Paul from the "new perspective". For Luther, the issue in Paul's writings is justification, or sinners being declared righteous before God on account of their faith in Christ. Luther's Paul opposed legalism, attempts to establish one's own righteousness before God through works. And Luther's reading of Paul helped him to overcome his own guilt-complex, for Luther had despaired of trying to establish his own righteousness as a monk, and so the notion of God's free offer of imputed righteousness by grace through faith was balm to his soul.
But advocates of the "new perspective" contend that Paul was concerned with other issues instead, such as the inclusion of the Gentiles into the people of God. Westerholm quotes E.P. Sanders as saying that Paul neither had a concept of imputed righteousness, nor did he have a problem with believers trying to live blameless lives. In Westerholm's scenario, Luther is baffled into silence as he encounters the new perspective, and he retreats to the "Self-Help" section of the bookstore.
I agree with Westerholm that Luther would have a problem with Sanders' dismissal of the concept of imputed righteousness. But I don't think that Luther would have a major problem agreeing that one of Paul's concerns was the inclusion of Gentiles into the people of God. Luther would probably wonder why some scholars believe that such a concern is so incompatible with his own belief that Paul was combating legalism and teaching that one is forgiven through faith, not works.
2. An interest of mine is whether Paul believed that the Torah was for Israel alone, or for Gentiles as well. Today, I read Westerholm's description of the views of Augustine, Martin Luther, and John Calvin on the law. Augustine and Luther believed that God had an eternal moral law, which was for all people. That law was included in the Mosaic law, which was for Israel only. Consequently, except for the Sabbath command (and, for Luther, the prohibition on graven images), the Decalogue is binding on Christians, since it contains the eternal moral law. But other parts of the Torah---such as the ceremonial law---are not binding on Christians, for it was for Israel alone and foreshadowed Christ. But Luther does maintain that non-Jews can get good ideas on laws for their state from the Mosaic code, even if it was only for Israel.
Calvin has a similar idea, but he holds that the moral law of the Torah was God's revelation of his will for humanity. For Calvin, the moral law is on the conscience of every human being, but God saw a need to reveal it on Sinai on account of human arrogance and dullness. The ceremonial law, however, was for Israel alone, and it foreshadowed Christ. God's covenant in the Old Testament was also with Israel alone, but, in the New Testament, it includes Jews and Gentiles.