Yea, brother: the particle nai is used in swearing, affirming, persuading, entreating, the latter seemeth here most proper; as much as, of all love, brother.
Let me have joy of thee in the Lord; it will rejoice my heart to see thee charitable and obedient to my monitions, let me have a spiritual joy from thy satisfying of me in what I desire.
Refresh my bowels in the Lord; either Onesimus, whom he had called his bowels, Phm_1:12; or, my inward man.