Philemon 1:6
That the communication of thy faith may become effectual by the acknowledging of every good thing which is in you in Christ Jesus. That the communication of thy faith may become effectual by the acknowledging of every good thing which is in you in Christ Jesus.
Paul's prayer for Philemon belongs to an affectionate greeting to him as friend and fellow worker, opening with a wish for grace and peace from God the Father and the Lord Jesus Christ, with thanksgiving and continual remembrance in prayer, and with joy over his love and faith toward the Lord Jesus and toward all the saints. In that setting, the sharing of his faith was to become effective as he acknowledged every good thing that was in him in Christ Jesus. Such effectiveness comes not from the believer's own goodness, but from recognizing that every good purpose and every trait of character in him is due to the grace of Christ, which alone makes him different from the perverse and the sinful.
For Philemon this meant recognizing Christ as the source of all the good in himself. That same grace was able to make a degraded criminal into a child of God and a useful worker for the gospel. In this setting that degraded criminal was the repentant slave Onesimus.