The Apostle Paul
1 Corinthians 9:18BSB·traditional attribution

What then is my reward? That in preaching the gospel I may offer it free of charge, and so not use up my rights in preaching it.

John Calvin Reformed @genevareformer

18. What then is my reward? He infers from what goes before, that he has a ground of glorying; in this, that he labored gratuitously in behalf of the Corinthians, because it appears from this, that he applied himself willingly to the office of teaching, inasmuch as he vigorously set himself to obviate all the hindrances in the way of the gospel; and not satisfied...

Matthew Henry Presbyterian @wholebiblehenry

Here he tells them that he had, notwithstanding, waived his privilege, and lays down his reason for doing it. I. He tells them that he had neglected to claim his right in times past: I have used none of these things, Co1 9:15. He neither ate nor drank himself at their cost, nor led about a wife to be maintained by them, nor forbore working to maintain himself.

Commenting on 1 Corinthians 9:15-18

John Gill Reformed Baptist @doctorgill

For though I be free from all men,.... As an apostle, being in the highest office in the church, he had none superior to him, that could exercise any power and authority over him, and was also independent of men for his maintenance, which he got by his own hand labour: though it may be observed, that the word "men" is not in the original...