Now when Peter had come to Antioch, I withstood him to his face, because he was to be blamed; for before certain men came from James, he would eat with the Gentiles; but when they came, he withdrew and separated himself, fearing those who were of the circumcision. And the rest of the Jews also played the hypocrite with him, so that even Barnabas was carried away with their hypocrisy. But when I saw that they were not straightforward about the truth of the gospel, I said to Peter before them all, “If you, being a Jew, live in the manner of Gentiles and not as the Jews, why do you compel Gentiles to live as Jews? (Galatians 2:11-14)
From very early on in Christian history there was a tension among believers (who were mostly Jewish) concerning Torah and whether with the coming of the Messiah it was still obligatory for Jews and mandatory for Gentiles converting to Christianity. Acts 15 presents one example of the tensions and controversy with the Apostles deciding the Torah was not mandatory for Gentile converts to Christianity.
Then of course the question arose as to whether it was still mandatory for Jewish Christians and this was a bit more contentious. As Jewish Christians attempted to span the divide between Gentile proselytes and practicing Jews a variety of methods were tried including living as a Gentile when with Gentiles and following Torah when with Jews. However, these efforts did not bring about the unity the Christians believed they were supposed to have within their communities as it left questions as to why God imposed the Law on Jews to begin with if in the end it wasn’t necessary for salvation. Biblical scholar Morna Hooker comments:
[The Apostles John and Paul] … both of them are using the idea of wisdom, which has come to be associated in Jewish thought with the Law. The divine plan was with God from the beginning, and was revealed to Israel on Sinai, just as the divine glory was reflected by Adam in the garden, and then glimpsed again when the Law was given.
Later rabbinic writings describe the Torah as having been hidden with God since before the creation. It is clear that for Paul the secret wisdom of God, hidden from creation and now revealed, is not the Law but Christ; he is the divine plan for mankind, the image to which we are being conformed, and the glory of God – and John expresses the same belief in his own terms. Over against the Jewish claim that God’s eternal purpose was finally revealed at Sinai, we have the Christian claim that the Torah only pointed forward to the revelation made in Christ. (FROM ADAM TO CHRIST, p 148)
Paul argues that Christ has both fulfilled the purpose of the Law and replaced it with the Gospel. The Law was meant as a temporary guide and teacher for the Jews, but with the coming of the Christ, the proper relationship with God was determined by the Gospel and one’s relationship to the Messiah and no longer by the Law whose purpose had been fulfilled and so was no longer necessary. Christianity has wrestled throughout its history with how much of the Law/Torah was obligatory for Christians. Some Christian groups have advocated for more adherence to the Torah as part of God’s eternal wisdom. The Apostles in Acts 15 require very little from the Torah not even demanding keeping the Ten Commandments, Sabbath observance, circumcision or Kosher/Kashrut diets. Paul and Peter’s public dispute over these issues are all part of the discussion/tension present in Christianity from its beginning. Christ fulfills Torah and many would say replaces it, yet for many Christians the exact relationship of the believer to Torah or to the Jews remains a point of debate. The tendency to see Christ as superseding Torah has contributed at times to anti-Semitism. Paul himself found it difficult to decide what the exact relationship of Christ or God to Jews who reject Christ is. At times he was exasperated by the Jews and at other times believed them to still be God’s chosen people with a God-given unique role in history no matter what their relationship to Christ is.
[Note in Acts 15 the Apostles together in council dealing with an issue which was tearing Christianity apart decide in order to fulfill the Gospel circumcision is not required of Gentile converts to Christianity. But in Acts 16:1-5, the first thing recorded after this Apostolic council is that Paul, a main advocate against having Gentiles circumcised, has Timothy circumcised! Paul struggled mightily with bridging that gap between Jewish and Gentile believers and appeasing all by trying to be all things to all people (1 Corinthians 9:22).
2nd Note: Some later Church Fathers were uncomfortable with Paul’s sharp words about Peter and the division it represented. In icons the two apostles are almost always shown hugging or cooperating in some manner. Some of these fathers tried to downplay the argument and re-interpret the event almost as if the apostles were only feigning the fight to prove other points. I take Paul at his word that he was really disturbed by what he saw Peter doing. Paul is known to have sharply disagreed with other church leaders as well (see Acts 15:2 and 15:39).]