John Calvin Commentary 1 Corinthians 9:23

"And I do all things for the gospel`s sake, that I may be a joint partaker thereof." — 1 Corinthians 9:23 (ASV)

That I may become a partaker of it. As the Corinthians might think to themselves that this was a peculiarity in Paul’s case because of his office, he argues, from its very design, that this is common to all Christians. For when he declares that his aim had been that he might become a partaker of the gospel, he indirectly intimates that all who do not act the same part as he does are unworthy of the fellowship of the gospel. To become a partaker of the gospel is to receive the fruit of it.