One of the reasons people find N.T. Wright confusing at times is that in one paragraph he seems to be affirming one thing and then with a statement he seems to deny it. In his response to John Piper Wright denies that the Jews of Paul's day were performing works of the law in order to earn favor with God. In one sense I agree with this. The Jews believed that they were God's covenant people. God gave them the law so that they would be God's special people, unlike any one else. They did not have legalistic intentions. However, to deny any sort of legalism seems impossible in light of what Wright says here:
"[Many Jews] would have taken the law and sung it to a tune like this. God gave Israel the Torah, the holy, just and good law. Israel is required to keep the Torah; those who do so will be vindicated as God's people when he acts in history to judge the nations and rescue Israel from their clutches. The way to tell, in the present, who will be vindicated in the future, is that they are keeping 'the works of the law' right now. That is their badge in the present, the present sign that they will be vindicated in the future" (Romans for Everyone p. 60).
When I read this, and other things from Wright, I scratch my head (not because I don't understand what he says; I don't understand why he denies certain things); I get that Jews believed that they were God's special people and some believed that if you wanted to be marked out as God's people you had to take on Torah. We need to take seriously Paul's discussion of how the law separates Jew and Gentile (or is God the God of the Jews only?). But what Paul denies is that the Jews could put any claim on God because they possessed and performed the law. They took pride in the idea that they were the ones obeying the law. They were God's privileged people. What does Paul say? "Now to the one who works, his wages are not counted as a gift but as his due. And to the one who does not work but believes in him who justifies the ungodly, his faith is counted as righteousness." Anytime, at least in my mind, people start saying things like, "we are A so we deserve B, we have A so we deserve B, or we have done A so we deserve B" there is, at least some sort, of legalism. We cannot expect vindication from God because of who we are, what we have, or what we have done. We are all under Sin's power. We all need to come to Christ in repentance and faith.