Tradition
St. Jerome
Against the Pelagians
Book II › Section 8
8. The Apostle confesses his need of this grace for his work.
1 Cor. i. 1-3. Grace to you from God.
7, 8. That ye come behind in no gift— that no flesh may glory in His sight.
1 Cor. iii. 6-10. Paul planted...but God gave the increase.
18, 19. If any man thinks himself to be wise, let him become a fool.
iv. 4. I know nothing against myself, yet I am not hereby justified.
Source: Against the Pelagians (New Advent)