Info:
To Paul was given the good news
of the cross. He was the first to preach it as God’s means of salvation – I Corinthians 15:3,4; Acts 13:38,39; Romans 3:21-28. It was the cross that made it possible for God to save all of man “freely by his grace through the redemption that is in Christ Jesus.” Paul’s gospel is called “the gospel of the grace of God.” According to that gospel there is no works for salvation – Romans 4:4,5; Ephesians 2:8,9.
https://rightlydividing.org/articles/baptism/why-did-paul-baptize-some/