Paul originally began Romans 3:2 with the exclamation, Therefore you have no excuse, O man, every one of you.
He explained how this truth applies to all nations (Romans 2:1–16), and now in this section specifically highlights how it applies to God’s privileged people, the Jews just as much as to others. The apostle thereby proceeds to provide his readers with arguments that they could use in the discussions with both Gentiles and Jews in the city of Rome. For them this passage also constituted a preliminary spiritual gesture from the apostle Paul in anticipation of his visit that they are expecting (Romans 1:11, Romans 15:15–17).1
10 as it is written: “None is righteous, no, not one;