One of the common themes in new perspective writings is that when Paul says we are not justified by works of the Law he does not have in mind the common Protestant claims that we do not earn our position before God or that we do not have to "do anything" for our salvation or similar conceptions that rely on the concept of "law" as something abstract, philosophical, or universal.
Instead, new perspective authors hold, the Law that Paul has in mind is something concrete and specific: the Mosaic Law or Torah.
Adherence to the Mosaic Law was constituitive of Jewish identity, and by saying that we are not justified by works of the Law what Paul was saying is that we are not justified by obeying the Mosaic Law, by being a faithful Jew.
Instead, we are justified through faith in Christ, through conforming to him rather than to the Mosaic Law.
He then quotes Pope Benedict XVI in a recent address from his weekly catechetical instructions:
So what does the Law from which we are liberated and which does not save mean? For St Paul, as for all his contemporaries, the word "Law" meant the Torah in its totality, that is, the five books of Moses. The Torah, in the Pharisaic interpretation, that which Paul had studied and made his own, was a complex set of conduct codes that ranged from the ethical nucleus to observances of rites and worship and that essentially determined the identity of the just person. In particular, these included circumcision, observances concerning pure food and ritual purity in general, the rules regarding the observance of the Sabbath, etc. codes of conduct that also appear frequently in the debates between Jesus and his contemporaries. All of these observances that express a social, cultural and religious identity had become uniquely important in the time of Hellenistic culture, starting from the third century B.C. This culture which had become the universal culture of that time and was a seemingly rational culture; a polytheistic culture, seemingly tolerant constituted a strong pressure for cultural uniformity and thus threatened the identity of Israel, which was politically constrained to enter into this common identity of the Hellenistic culture. This resulted in the loss of its own identity, hence also the loss of the precious heritage of the faith of the Fathers, of the faith in the one God and in the promises of God.I find all of this quite exciting. I have never been able to slog through the usual faith vs works arguments or apologetics. I am heartened, in this year of St. Paul, by the new Pauline scholarship emerging from both Catholic and Protestant circles. I also love the new biblical scholarship that incorporates historical-critical methods but allows them their proper role instead of elevating them beyond what is reasonable as was done in the latter half of the 20th century.
Against this cultural pressure, which not only threatened the Israelite identity but also the faith in the one God and in his promises, it was necessary to create a wall of distinction, a shield of defence to protect the precious heritage of the faith; this wall consisted precisely in the Judaic observances and prescriptions. Paul, who had learned these observances in their role of defending God's gift, of the inheritance of faith in one God alone, saw this identity threatened by the freedom of the Christians this is why he persecuted them. At the moment of his encounter with the Risen One he understood that with Christ's Resurrection the situation had changed radically. With Christ, the God of Israel, the one true God, became the God of all peoples. The wall as he says in his Letter to the Ephesians between Israel and the Gentiles, was no longer necessary: it is Christ who protects us from polytheism and all of its deviations; it is Christ who unites us with and in the one God; it is Christ who guarantees our true identity within the diversity of cultures. The wall is no longer necessary; our common identity within the diversity of cultures is Christ, and it is he who makes us just. Being just simply means being with Christ and in Christ. And this suffices. Further observances are no longer necessary.