1 Corinthians 15:10
10 But by the grace of God I am what I am, and his grace toward me was not in vain. On the contrary, I worked harder than any of them, hthough it was not I, but the grace of God that is with me.
Galatians 2:2
2 I went up because of a krevelation and set before them (though privately before lthose who seemed influential) mthe gospel that I proclaim among the Gentiles, in order to make sure I was not running or had not run nin vain.
1 Thessalonians 3:5
5 For this reason, when I could bear it no longer, I sent to learn about your faith, for fear that somehow the ntempter had tempted you and our labor would be oin vain.