John Calvin Commentary Philemon 1:6

"that the fellowship of thy faith may become effectual, in the knowledge of every good thing which is in you, unto Christ." — Philemon 1:6 (ASV)

That the communication of your faith may be effectual. This clause is somewhat obscure, but I will endeavor to elucidate it so that my readers may better understand Paul’s meaning. First, it should be known that the Apostle is not continuing to praise Philemon but, on the contrary, is expressing those blessings for which he prays to God. These words are connected with what he had previously said, that he makes mention of him in his prayers (Philemon 1:4). What blessing then did he ask for Philemon?

That his faith, by exercising itself through good works, might be proven to be true and not unprofitable. He calls it “the communication of faith” because it does not remain inactive and concealed within but is manifested to people by actual effects. Although faith has a hidden residence in the heart, it still communicates itself to others through good works. It is, therefore, as if he had said, “That your faith, by communicating itself, may demonstrate its efficacy in every good thing.”

The knowledge of every good thing denotes experience. He wishes that, by its effects, faith may be proven to be effectual. This takes place when the people with whom we converse know our godly and holy life; and therefore, he says, of every good thing which is in you; for everything in us that is good makes known our faith.

Towards Christ Jesus. The phrase εἰς Χριστόν may be explained to mean “through Christ.” But, for my own part, if I had the freedom, I would rather translate it as equivalent to ἐν Χριστῷ, “in Christ.” For the gifts of God dwell in us in such a way that we are, nevertheless, partakers of them only to the extent that we are members of Christ. Yet because the words in you come before, I am afraid that the harshness of the expression would cause offense. Accordingly, I have not ventured to change the words but only wanted to mention this to my readers, so that, after careful consideration, they may choose whichever of these meanings they prefer.