Paul's credentials were verified by the results achieved.
(2 Corinthians 3:1-3) Are we starting to recommend ourselves again? Or do we need, like some men, letters of recommendation to you or from you? You yourselves are our letter, inscribed on our hearts and known and being read by all mankind. For you are shown to be a letter of Christ written by us as ministers, inscribed not with ink but with the spirit of a living God, not on stone tablets but on fleshly tablets, on hearts.
