1 Corinthians 9:20-21 — Paul uses "under the law" four times, clearly meaning Jews/Jewish law observance

1 Corinthians 9:20-21: "To those under the law I became as one under the law (though not myself being under the law) that I might win those under the law. To those outside the law I became as one outside the law…" Paul is describing his missionary approach to Jews (under the law) versus Gentiles (outside the law). He then adds two caveats: (1) he is not personally under the law; (2) he is not lawless before God but is under the law of Christ.