After Paul’s supernatural change from Saul to Paul, is it possible that his missionary life would have been the most Christlike besides the savior himself?
I don’t know that it was a supernatural change that happened as far as Paul’s name change. His experience with the Lord on the road to Damascus in Acts 9 was a supernatural event that totally transformed his life.
He went from being the persecutor of Christians to the apostle to the Gentiles on behalf of Christ and his church. However, his name did not change until later in the book of Acts. The change happens in Acts 13:9. He is given both names and then is only referred to as Paul.
Many scholars believe that Paul used both names in different contexts. They suggest that Saul was his name when he was a month the Jews. But when he was in the string for the Lord as the apostle to the Gentiles, he used the name Paul instead. They suggest that Saul was his Jewish and Paul was his Roman name.
As far as his missionary journeys, of which there were at least three and more likely four, Paul experienced God’s power in extremely great ways. He even had the experience of visiting the third heaven where God dwells (2 Corinthians 12).
He suffered a great deal as he traveled for the gospel and ended up in chains for the gospel. All of his suffering and the glory he saw made him one of the most interesting people in the New Testament.
As far as being the most Christlike, throughout the New Testament we need apostles and saints who all demonstrate to us what it is like to be like Christ. Not only through teaching, but also through their ministries and actions, these great men and women of God show us what it means to follow hard after Christ and live for him.