1 Corinthians 15:9-11 (NRSV)
9 For I am the least of the apostles, unfit to be called an apostle, because I persecuted the church of God. 10 But by the grace of God I am what I am, and his grace toward me has not been in vain. On the contrary, I worked harder than any of them—though it was not I, but the grace of God that is with me. 11 Whether then it was I or they, so we proclaim and so you have come to believe.