Chapter two records yet another visit Paul made to Jerusalem, this time with Barnabas and Titus (Galatians 2:1-5). The fact that Titus is never mentioned in Acts makes it difficult to make certain determination, but the “fourteen years” Paul mentioned makes it possible that this was the famine relief visit in Acts 11:30. This is preferred because this visit was “only…a private meeting with the influential people” rather than all the apostles and elders and congregation at the Jerusalem Council. In this meeting Paul made sure to emphasize that he preached justification by grace through faith and did not insist on circumcision for Gentiles (Galatians 2:6-10). The other apostles agreed with his message and agreed that he and Barnabas “would go to the Gentiles and they to the circumcised.” (This also implies that their Acts 13-14 missionary tour had not taken place yet.)
In a show of “goodwill” for Paul and Barnabas’ ministry in Antioch, Peter made a visit there (Galatians 2:11-14). Although he had good relations with them for a while, including eating meals with them, when “certain people came from James” he began to pull away from the Gentiles. This hypocrisy grew to such a level “that even Barnabas” got caught up in it. Because of the public humiliation these Jews imposed on their Gentile brothers, Paul publicly called them out.
Paul used this event to segue into his first major doctrinal statement of the letter’s body and introduced his main thesis: “We know that no one is justified by the works of the law but by the faithfulness of Jesus Christ” (Galatians 2:16). To the Jews were given the covenants, promises, etc. (Romans 9:1-5), and Jesus said that “salvation is from the Jews” (John 4:22). Paul’s emphasis that he was a Jews “by birth” (literally, “by nature”) rather than “by conversion” was to show that he was not justified by any of those. Even a Jew must believe in Jesus.
One debated point in this passage and several others in Paul’s writings has to do with the phrase “the faithfulness of Jesus.” Although this is the best translation of the Greek text, most translations offer “faith in Jesus.” This seems to do damage to Paul’s meaning, emphasizing our faith rather than his work. Many other works have been written on this, and it is impossible to work through all of the debate here.