Paul fought with Peter in Antioch after men from James arrived there. Oceans of ink have been spilled trying to account for the causes of their fight. Because of one prominent scholarly tradition of interpretation, James and Peter have long been cast as conservative, Law-observant apostles, “Jewish  Christians” who wanted Christ-following gentiles to be circumcised. Paul, by contrast, is the “Law-free” radical who insists that gentiles (and, in some readings, Jews too) be unencumbered by Law-observance. And this reconstruction presupposes that Paul, too, had stopped living a Jewish life. He thereby transmutes from being a “Jewish” Christian into a sort of honorary gentile one, as well as the premier defender of and spokesman for a “Law-free” gentile Christianity. 

This interpretation misreads all parties. From the beginning—before Paul was even involved—the movement had admitted gentiles without requiring them to be circumcised. James, Peter, and John all affirmed that position, back in Jerusalem. But these gentiles were responsible for maintaining some specifically Jewish behaviors, such as worshiping only Israel’s god (sic), and renouncing sacrifices made to idols. All the apostles, Paul included, were agreed on this, and in this sense no form of the gospel, for gentiles, was “Law-free.” And finally, Paul, as we have seen, worked in concert with James about the collection for the Jerusalem community throughout the rest of his missions. No ideological breach yawned between the two men. -Paula Fredricksen, When Christians Were Jews, p.160-161