Focus on verse 10-11
Someone once explained it to me this way; when you do something for another person, it is like you have some change in your pocket which is worth something to that person. Conversely when you ask that person for a favor, some of that is used up in the transaction, and that person now carries a small amount of change in their pocket which is worth something to you.
In today’s reading, Paul calls in a favor from an old friend on behalf of a third party.
I appeal to you for my child, Onesimus, whose father I became in my imprisonment. (Formerly he was useless to you, but now he is indeed useful to you and to me.) (v. 10-11)
Apparently what had transpired was that Philemon, who was a follower of Jesus, as well as a friend and supporter of the Apostle Paul had a slave named Onesimus who had stolen some property from Philemon and run away. This was a crime that had severe consequences if the runaway was caught.
It just so happened that God arranged for Onesimus to encounter Paul, who introduced Onesimus to Christ. Paul further challenged Onesimus to return to Philemon to make right the wrong of running from his master. Paul also send a letter along with Onesimus encouraging Philemon to forgive Onesimus and accept him back as a brother in the Lord rather than a slave.
The lesson for us in this short little letter gives us a small picture of how to manage conflict in Christian relationships. I sometimes get the impression that there is this expectation that there should be be no conflict among those who follow Jesus. While it is true that the presence of the Holy Spirit in our lives does much to foster forgiveness and unity, it would be unrealistic to expect all conflict to somehow instantaneously vanish from our relationships. What we should expect is for the love and grace of God within us to have a strong influence in the manner in which we respond to conflict when it occurs.
It is exactly this that Paul expects from Philemon and Onesimus. The conflict is obvious, but this solution to the conflict is radically different from what the cultural norm would have expected and allowed. In that culture, when runaway slaves were caught, they were typically made an example by some public form of punishment to discourage other slaves from attempting the same. This punishment ranged from a severe beating to execution. For Philemon to not only accept Onesimus back as a slave by to treat him as an equal undoubtedly made a radical statement to the community that was expecting a different outcome. I suspect Paul was asking Philemon to do this not just for the sake of Onesimus, but for the sake of the testimony this act would have within the church and community to which both men belonged.