The church throughout history has mostly misunderstood Paul, thinking that he taught the law was obsolete. ironically, the book of Acts records that in his own day he was misunderstood as having taught this very thing and he adimately denied teaching such:
"After greeting them, he related one by one the things that God had done among the Gentiles through his ministry. And when they heard it, they glorified God. And they said to him, “You see, brother, how many thousands there are among the Jews of those who have believed. They are all zealous for the law, and they have been told about you that you teach all the Jews who are among the Gentiles to forsake Moses, telling them not to circumcise their children or walk according to our customs. What then is to be done? They will certainly hear that you have come. Do therefore what we tell you. We have four men who are under a vow; take these men and purify yourself along with them and pay their expenses, so that they may shave their heads. Thus all will know that there is nothing in what they have been told about you, but that you yourself also live in observance of the law. But as for the Gentiles who have believed, we have sent a letter with our judgment that they should abstain from what has been sacrificed to idols, and from blood, and from what has been strangled, and from sexual immorality.”
Peter also seems to allude to this mischaracterization of Paul:
And count the patience of our Lord as salvation, just as our beloved brother Paul also wrote to you according to the wisdom given him, as he does in all his letters when he speaks in them of these matters. There are some things in them that are hard to understand, which the ignorant and unstable twist to their own destruction, as they do the other Scriptures.
2 Peter 3:15-16 ESV
Paul, taught a historic Jewish position, although controversial in his time, that non-Jews did not need to (and according to him should not) under go proselyte conversion to become Jews, in order to become part of the people of God (which also know a different Torah obligation as Gentiles aren’t oblugated to keep asoects of the Torah that are specific to Jews in the way a Jew isn’t obligated to keep laws specific to priests, or a priest laws specific to woman.)
To him this was an afront the the oneness of God as stated in the Shema (the Lord is one), “is God the Gid of Gentiles also, is he not the God of Jews also.”, as well as thr promise to Abraham of his seed being a blessing to all nations (if Gentile all became Jews how could this promise become true?)
It was primarily these issues that Paul addresses in Romans and Galations and he emphasizes that both Jews and Gentiles are saved by grace and made holy and part of the the people of God by the Holy Spirit. He uses several Grecko-Roman oral rhetoric techniques as well as several Jewish rabbinical teaching methods that often resukt in misunderstanding to those unfamiliar with them.
Acts makes clear though that he remained a Torah observant Jew his whole life and never taught his fellow Jews to do otherwise after confessing Jesus as Lord. He is even recorded in Acts 18 as taking leave during his missionary journey to Ephasis to go back to Jerusalem to celebrate Pentecost.