1 Corinthians 15:10-14

But by the grace of God I am what I am, and His grace toward me did not prove vain; but I labored even more than all of them, yet not I, but the grace of God with me.

Whether then it was I or they, so we preach and so you believed.

Now if Christ is preached, that He has been raised from the dead, how do some among you say that there is no resurrection of the dead?

But if there is no resurrection of the dead, then not even Christ has been raised;

and if Christ has not been raised, then our preaching is in vain, your faith also is in vain.