One of the hardest things to do in life is to own up to one's mistakes and the consequences of them. The difficulty is increased when the consequences involve reimbursing another person, and it is increased again when one has already become far removed from the situation. Onesimus had gotten himself into this very situation. He had broken from his service to Philemon and fled to Rome. While he was in Rome, however, he met the apostle Paul, and he became a believer. Onesimus then developed a conviction to return to his master, whom Paul knew personally, to be reconciled to him. So Paul sent him back with a letter to his master, Philemon.
Few specifics are mentioned in this letter or the New Testament concerning Onesimus's actions, how he met Paul, or how long he was in Rome. It does not seem possible that Onesimus had gone only as far as Ephesus and still met Paul, since Paul claimed to have converted him while in chains. It is equally doubtful that Onesimus was arrested and imprisoned with Paul, since according to Acts 28:16 Paul was only under house arrest. According to James D. G. Dunn, Lightfoot Professor of Divinity at Durham, the simplest explanation is that "Onesimus left his master's household with the express purpose of contacting Paul" (304) in order that Paul might intercede on his behalf to Philemon.
Verse 18 implies that Onesimus had stolen from Philemon, or at least that such an accusation could have been entertained. Professor at Mid-America Baptist Seminary of New Testament and Greek, Richard R. Melick, Jr., recorded these potentialities: "Most commonly, scholars assume that he had stolen money and then absconded (v. 18). Others suggest that he only owed Philemon the value of the work that would have been done in his absence" (Dockery 337). Whatever the circumstance, amends needed to be made between Onesimus and Philemon.
In order to make Philemon as receptive and gracious to Onesimus as possible, Paul commends Onesimus five times. First Paul calls him "my child, whom I gave birth to" (not "have begotten" as Lenski urges, 962). Onesimus was now a believer. "Paul places these words before the name 'Onesimus' so that they may immediately touch Philemon's heart" (Lenski 962).
Next Paul highlights Onesimus's usefulness. Formerly, he had been useless to Philemon, most likely a reference to his running away and possible theft, but now he would be of "good use" not only to Philemon but also to Paul. AcrhstoV and eucrhstoV are employed here to play on words; the name "Onesimus" means "useful." Also, several commentators note the hint toward CristoV, which might indicate that Onesimus's usefulness was being determined in relation to the gospel as opposed to his labor.
Then Paul equates Onesimus with his inmost self. The word splagcna literally means "inward parts" but represents deep-seated emotion. Paul had come to love this slave in a unique way and was concerned for his future. Philemon could not possibly overlook such strong language from Paul on behalf of Onesimus.
Fourthly, Paul was thinking about holding Onesimus back from returning in order that he might continue to serve Paul. "The imperfect tense ("I was wanting") implies a period during which Paul weighed the consequences of his action and during which the value of Onesimus's presence was a considerable factor in his deliberation" (Dunn 330). Dunn also points out the emphatic egw, indicating that Paul (and not Onesimus) was reluctant concerning the departure, and the understanding of katecw to mean "to hold back, prevent from leaving" (330).
Lastly, Paul appeals to Philemon based on his new brotherhood with Onesimus. They are no longer only master and slave but also brothers, hinting at the kind of "one another" fellowship that they should secure. In fact, Philemon's relationship with Onesimus should become stronger now than Paul's relationship with Onesimus.
In application, the most significant issue here is not reconciliation but personal evangelism. Paul puts a simple faith in Christ on a pedestal and claims that it makes all the difference in the world! Sinners who were of "no use" now will be put to "good use," and more than that, they become as family to us. If we today only kept these two things in mind, we would be far more adamant and effective in our efforts to disciple new believers.
Paul also displays here a sign of good leadership: emphasize the strengths. Onesimus had not suddenly been transformed into a perfect man, nor was the past erased at the moment of his conversion, but he was a believer apparently intent on living like one. Emphasizing the strengths of a person or situation is not only encouraging but it also takes the focus away from only the negative aspects, the mistakes/wrongs, the weaknesses.