Galatians 2:15 Meaning and Explanation

Paul begins his argument by standing with Peter on common ground. They were both Jews by birth, raised inside the covenant, not outsiders. He grants every advantage of that heritage before making his point.

The phrase 'sinners of the Gentiles' reflects how the nations were often viewed from within the law. Paul names this starting position precisely so he can overturn the assumption that goes with it. Even those with every religious advantage, he is about to say, are not made right with God by that advantage.