1 Corinthians 15:9-10

Amplified Bible

⁹ For I am the least [worthy] of the apostles, and not fit to be called an apostle, because I [at one time] fiercely oppressed and violently persecuted the church of God. ¹⁰ But by the [remarkable] grace of God I am what I am, and His grace toward me was not without effect. In fact, I worked harder than all of the apostles, though it was not I, but the grace of God [His unmerited favor and blessing which was] with me.