Saint Chrysostom says: “I pray, he says, ‘that the communion of your faith may become effective.’ In what and how? ‘In the knowledge of every good thing,’ that is, that you may attain every virtue and have no lack. Faith becomes effective when it is accompanied by works. For ‘faith without works is dead,’ Jas 2:26. He did not say, your faith, but ‘the communion of your faith,’ that is, your faith common with us. He joins him to himself and suggests that they are one body. By this he persuades him with special force. If, he says, you are my partner in faith, then you must also be my partner in everything else.”
Blessed Theodoret expresses the same thought in brief general words: “I both ask and pray the common Benefactor to grant you complete possession of the good things.”
Oecumenius introduces the interpretation word by word: “That the communion of faith.” By joining him to himself, the Apostle as though said: our common faith, which makes us common. But someone may ask: why do you thank God so, or for what do you pray so? He says: “That the communion of your faith may become effective.” How will it become effective? Through your knowledge and doing of every good thing, he says. “In Christ Jesus,” or for Christ Jesus. For whoever does good to someone does it to Christ, especially when he does it to His saints.
Blessed Theophylact collected all the thoughts set forth and offers them in this form: “The Apostle says: I thank God for your love, praying also that your faith, which you have in common with us, may be ‘effective,’ active and alive in your knowledge of every good deed. That is, in your loving it and bringing it into action. For faith is alive when we devote ourselves to every good deed, just as it is dead when it is without good works. The Apostle added, ‘which is in you,’ in order to show that Philemon already has every good deed in himself, as though saying: in the knowledge of every good deed that is already in you, that is, in you yourself. Having said ‘communion of faith,’ Saint Paul joins Philemon to himself and makes him one. The common faith is also one-making, so that you must also be of one mind with me, regarding things and persons as I do. Or by communion of faith he means almsgiving that comes from great faith. Thus the Apostle says: I make remembrance of you, praying that your communicative and generous disposition may never cease, but that you may pour out more and more every good thing upon the needy, ‘which is in you,’ that is, which you possess. ‘In Christ Jesus.’ Every good thing you do to the needy, especially to the saints, is lifted up to Christ Jesus. So now, if you receive Onesimus and give me joy, you will do it to Christ Himself.”
If these words are referred to Philemon, the flow of thought will be as follows: I thank God in my prayers for you, hearing of your love and faith toward the Lord and the saints, which you have because you are moved not to let your faith remain idle and ineffective, but always to keep it active.
“The communion of faith” will then mean that you abandoned paganism and entered into communion with the Lord and with those who believe in Him. You became a participant in the Christian faith.
Having participated in the one true faith, you were zealous and remain zealous that it not be idle and ineffective in you, but effective. You are not content to be a Christian in name only. You are zealous to be one in deed, truly such as this faith requires.
What moves and inspires him to live and act so? The consciousness of the great good things received from faith. The word “in knowledge” means in recognition, in consciousness.
Having understood and being conscious of how many good things he received by believing in the Lord, he himself is zealous for every good. He is zealous to act, so that his faith may be effective, and so that he may show himself fruitful, not having been granted communion of faith in vain.
He says: in the consciousness of “every good thing.” Not one good thing was received, but every good thing: forgiveness of sins, knowledge of the truth in its fullness, and the grace of the Holy Spirit, which builds good dispositions in the heart. There are also peace and joy in the Spirit, and above all the unfailing promise of the inheritance of the Kingdom of Heaven, with faithful firstfruits of it already here.
Being conscious of all this, you are zealous to appear grateful to the Benefactor by doing every good.
“Which is in you.” You do not see such good things in others, as if from afar. They are before your eyes, in each of you and in yourself. Instead of “in you,” some now read “in us,” understanding Christians in general. Spiritual good things from the faith of Christ were everywhere, and everyone experienced them.
In answer to the question why you went over to the Christians, one could boldly reply: do you see how many good things it gives? How could one not prefer it to all other faiths?
In connection with the phrase “in the knowledge of every good thing,” another thought is also possible: that other people who do not yet believe may be made to understand how many good things are in our faith. By this they may be disposed to recognize it as the one true faith, and to come over and cleave to it.
“In Christ Jesus” can be understood in two ways. It may be connected directly with the preceding words: in the consciousness of every good thing received in Christ Jesus, according to the divine economy of salvation accomplished and established by Him.
Or “in” may be left in its own sense, as indicating the aim and direction of deeds. Then it must be referred to “may become effective”: that the communion of your faith may become effective for Christ Jesus, for pleasing Him, for the glory of His name, and for assisting the work of the salvation of all, accomplished and being accomplished by Christ Jesus.
THEOSIS