Paul reminds them of his credentials: At one time, Paul had been instrumental in the attempt to halt the inroads of the Christian message into Judaism. Then, God told him to preach to Gentiles, to tell them about Jesus Christ.
Although he began his travels without prior conference with the central church in Jerusalem, he did at a later point meet with Peter and with James, the brother of Jesus.
Paul's understanding is that Gentiles do not have to become Jews in order to be Christians. The disciples who have been upsetting the Galatians disagree. They have been trying to convince the Galatians that being a Jew is an entry requirement.
Paul himself never quit being a Jew. But, he did not restrict Christianity to Jews alone.
Paul's idea has won out over that of those false apostles to Galatia. Yet, we still are being confronted by those who think our way of being Christian is not strict enough, not close enough to the Scriptures. Or, we may be in the strict group that is preaching to those who are not living up to what appears to be very scriptural. How could they? Complainers and complainees need to spend some time with this letter.
On the United Methodist Church website under the tab Our People, I read:
The People of The United Methodist Church
Help people in their community
Accept you for who you are
Offer a place to belong
Care for and support each other
Show respect for other religions
Support people facing difficulty
Welcome diverse opinions and beliefs
Guide others to find deeper meaning