1 Corinthians 9:17-19 New Matthew Bible (NMB)
17 If I do it with a good will, I have a reward. But if I do it against my will, an office is committed to me. 18 What is my reward then? Truly, that when I preach the gospel, I make the gospel of Christ free: that I do not misuse my authority in the gospel.
19 For though no man is my master, yet I have made myself a servant to all, so that I might win the more.