Here Paul established the basis of his standing before God. It was not his merit. His salvation came despite his condition as a sinner. He described his pre-conversion life and person by writing he was a blasphemer, persecutor, insolent, and ignorant. In fact, he wrote, “Christ Jesus came into the world to save sinners, of whom I am chief” (vs 15).
Despite Paul’s shortcomings and sin, Jesus Christ chose him to be an apostle. It is understandable that Paul would state that the grace of the Lord (freely given gift) was “exceedingly abundant” toward him.
The phrase, “because I did it ignorantly in unbelief.” Does indicate the good conscience of Paul (cf. Acts 23:1), but good intentions do not equal acceptance. Paul had to do what everyone has to do to receive that grace from God. (We can read from Acts 9 and Acts 22 to see what that was).
God grants second chances (and more) to the penitent and honest individuals who want to change and serve him. If he did it for Paul (chief among sinners), he will do it for anyone.
