9:15-23 It is the glory of a minister to deny himself, that he may serve Christ and save souls. But when a minister gives up his right for the sake of the gospel, he does more than his charge and office demands. By preaching the gospel, freely, the apostle showed that he acted from principles of zeal and love, and thus enjoyed much comfort and hope in his soul. And though he looked on the ceremonial law as a yoke taken off by Christ, yet he submitted to it, that he might work upon the Jews, do away their prejudices, prevail with them to hear the gospel, and win them over to Christ. Though he would transgress no laws of Christ, to please any man, yet he would accommodate himself to all men, where he might do it lawfully, to gain some. Doing good was the study and business of his life; and, that he might reach this end, he did not stand on privileges. We must carefully watch against extremes, and against relying on any thing but trust in Christ alone. We must not allow errors or faults, so as to hurt others, or disgrace the gospel.

19. free from all men—that is, from the power of all men.

gain the more—that is, as many of them ("all men") as possible. "Gain" is an appropriate expression in relation to a "reward" (1Th 2:19, 20); he therefore repeats it frequently (1Co 9:20-22).