Philem 15-19 (NIV) Perhaps the reason he was separated from you for a little while was that you might have him back for good— 16 no longer as a slave, but better than a slave, as a dear brother. He is very dear to me but even dearer to you, both as a man and as a brother in the Lord.
17 So if you consider me a partner, welcome him as you would welcome me. 18 If he has done you any wrong or owes you anything, charge it to me. 19 I, Paul, am writing this with my own hand. I will pay it back — not to mention that you owe me your very self.
NOTE: Paul says that Onesimus returns no longer as a slave but as a dear brother. But the fact that he returns shows that he is, in a sense, still a slave. As a slave, he has an obligation to his master. And Paul returns him so that he can fulfill his obligation. In the Jewish system, individuals sold themselves for a period of time for cash and work, much like the current system of sports contracts. At the end of the contract, they were free to pursue another contract. There were also other types of slave contracts where individuals were treated as property with little benefit to the individual. It is not clear under which system Onesimus was. Also, Paul agrees to pay any expense that Onesimus has caused. In both cases, Paul gives importance to the issue of obligation. In fact, Paul ends by reminding Philemon of his obligation to Paul. God obviously considers our contractual and financial obligations, as well as our promises of key importance. As believers, we have a moral duty to fulfill our obligations--it is part of our witness as believers. What have I promised that I have not fulfilled?