For a definition of “grace” see on Rom. 3:24. All that Paul had become or had achieved in the Lord’s service he attributed to the unmerited mercy, favor, and power of God. He had learned the essential lesson that all human accomplishments are valueless in the work of God if separated from an impartation to the soul of that spiritual life from God that is called “grace.” Paul knew that all his zeal, piety, abilities, and success as an apostle were the result of the undeserved favor God had manifested toward him. By God’s grace he had been enabled to accomplish more than the other laborers.

A note of thankful relief creeps into Paul’s words here—he is glad God’s grace was not wasted when bestowed upon him.

That is, worked harder. Consecration and hard work rarely fail to produce abundant fruitage. But, as the next phrase reveals, the apostle allowed no overwhelming pride to mar his evangelistic success.

 Paul left no room for anyone to imagine that he took credit to himself; he gives all the glory to God. All who achieve true success in the work of God on earth will acknowledge that any good they have accomplished has resulted from God’s enabling grace (cf. Gal. 2:20; Phil. 2:13; 4:13).

The phrase stresses the condition of Paul’s spiritual state, and contains no boastful egotism.