This is one of Paul's prison letters written to a Christian brother named Philemon. The reason Paul wrote this letter was that he had a slave named Onesimus who had run away from Philemon. He ended up in Roma where Paul was in prison. Since he found Paul, he had become a Christian and accepted Christ as his savior. Paul convinced him to go back to his master and make things right. I find it interesting how Paul talks with Philemon. He is very psychological with him. We must be wise when we want to convince someone of what is needed. Paul uses an excellent appeal method to do just that. Paul did mention that he would have liked for Onesimus to have stayed there with him, but he would do nothing without the consent of Philemon and giving him the final say on the matter.
Onesimus gets a good report in Paul's letter to the Colossians (Col 4:9). I don't know the dates of that letter but it wouldn't surprise me if Philemon didn't send him back to Paul. What a good report about him in this passage. When all is said and done, I wonder what someone like Paul would say about me? It does matter what kind of a testimony of Christ we will have. It will be revealed one day at the judgement seat of Christ.