John Calvin Commentary 1 Corinthians 9:19

"For though I was free from all [men,] I brought myself under bondage to all, that I might gain the more." — 1 Corinthians 9:19 (ASV)

Though I was free from all. Εκ πάντων, that is, from all, may be understood in either the neuter or the masculine gender. If in the neuter, it will refer to things; if in the masculine, to persons. I prefer the second. He has so far shown by only one particular instance how carefully he had accommodated himself to the weak.

Now he adds a general statement, and afterwards enumerates several instances. The general observation is this: while he was not under the power of anyone, he lived as if he had been subject to the inclination of all, and of his own accord subjected himself to the weak, to whom he was under no subjection.

The particular instances are these: among the Gentiles he lived as if he were a Gentile, and among the Jews he acted as a Jew. That is, while among Jews he carefully observed the ceremonies of the law, he was no less careful not to cause offense to the Gentiles by observing them.

He adds the particle as to indicate that his liberty was not at all impaired on that account; for, however he might accommodate himself to people, he nevertheless always remained himself inwardly in the sight of God.

To become all things is to assume all appearances, as the case may require, or to put on different characters, according to the diversity among individuals.

Regarding what he says about his being without law and under the law, you must understand this simply in reference to ceremonial matters. For moral matters were common to Jews and Gentiles alike, and it would not have been permissible for Paul to gratify people to that extent.

For this doctrine applies only to indifferent matters, as has been previously remarked.