Summary: Paul gives the history of how he changed from being zealous for Jewish traditions to getting revelation from God about Jesus Christ without having contact with any of the apostles to teach him. He emphasizes that even those regarded as pillars of the faith have no special standing with God compared to others who have faith in Christ, and he reiterates that the law (including circumcision) has nothing to add to the Good News of Christ.
Why I read from the World English Bible
I read from the 2016 edition, linked to below:
There is also a 2019 edition:
There is also a 2019 edition: