"For this may be why he was some time separated from thee : that thou mayest possess him for ever, no more as a slave, but above a slave, as a beloved brother "Philemon v. 15, 16
The apostle Paul is imprisoned in Rome when he writes a short letter to a certain Philemon, a Christian of Colossus in present-day Turkey. At that time, slavery was a social reality in the Roman Empire. Paul evokes it in this letter, for he speaks of a new convert dear to him : Onesimus ; But for Philemon, this Onesimus is a deserting slave !
Paul was an actor in the conversion of Onesimus : "I pray you for my child whom I have begotten, being in chains" (v. 10). He also knows Philemon well, "our beloved companion of work" (v. 1).
Paul is faced with a dilemma. He needs Onesimus : "I would have liked to hold him close to me, that he might serve me in your place when I am chained because of the gospel" (v. 13). On the other hand, he acknowledges that the desertion of Onesimus is a sin against Philemon. How can we account for the social realities of the time, while at the same time encouraging Philemon, a trafficked master, to act as a Christian ? To do this, he does not use his status as an apostle ; He does not give him a lesson or order, but humbly begs him to receive Onesimus as a brother, wishing that he will not act under the effect of coercion but of his good will. Paul acknowledges the authority and rights of Philemon : "I did not want to do anything without your advice" (v.14). He even suggests that the flight of his slave may be advantageous to Philemon : "For this may be why he was some time separated from thee: that thou mayest possess him forever, not as a slave, But above a slave, as a beloved brother" (15:16).
To superimpose a fraternal relationship to the legal relationship of a slave-master fundamentally upsets the situation and re-establishes Onesimus in his dignity as a man, without withdrawing him from his service. By receiving Onesimus with love, Philemon will honor the Gospel.
Paul's approach shows us how to act in difficult relationships. It encourages us not to use moralist speech, to forget our status ; It encourages us to limit ourselves to inviting our neighbors to act following Jesus in love and forgiveness, while showing the example of our behavior.
Source (To pleasing the Lord)