1 Cor. 1:17
17 For Christ did not send me to baptize, but to preach the gospel--not with words of human wisdom, lest the cross of Christ be emptied of its power.
1 Cor. 15:1-4
1 Now, brothers, I want to remind you of the gospel I preached to you, which you received and on which you have taken your stand. 2 By this gospel you are saved, if you hold firmly to the word I preached to you. Otherwise, you have believed in vain. 3 For what I received I passed on to you as of first importance: that Christ died for our sins according to the Scriptures, 4 that he was buried, that he was raised on the third day according to the Scriptures,
23 if you continue in your faith, established and firm, not moved from the hope held out in the gospel. This is the gospel that you heard and that has been proclaimed to every creature under heaven, and of which I, Paul, have become a servant.