I wrote this real quick sorta on the plane yesterday and sorta not…. so… sorry….
That the open theme in Philemon is connected to slavery is nothing new and has been seen in a variety of ways including Paul’s near condemnation of the practice by various interpreters; however, I have come to compare it with Dio Chrysostom’s letter to the Prusites, his letter of friendship as it were, and find that Paul may be saying more than what some have given him credit for or have denied to him.
In the recent Two Horizon’s commentary, Marianne Meye Thompson compares Paul’s letter to Philemon to Pliny’s letter to his friend Sabinianus which oddly enough involved much to the same situation in that a runaway slave had come to Pliny only to be sent back to the former master with a letter in hand. Pliny, like Paul in 1.8-9, even suggests that he would only request, rather than command, that the slave be forgiven. Paul remained cordial and polite, perhaps trying to invest into the letter a sense of the client-patron system. We may see some of this in Paul’s drawing near to Philemon as a friend and reminding him that Philemon owes to Paul his own self. While we do not see the same overt plea to friendship in Paul’s letter as we do in Dio Chrysostom’s plea to his home city not to engage in an independence movement, I believe that Paul’s push to rely on Philemon’s friendship is clear. It is this friendship then, whether couched in the familiar patron-client relationship or Dio Chrysostom’s friendship epistles that suggests that while Paul does not explicitly ask for Onesimus’ release, he never the less would want nothing less than freedom for the escaped slave.
“Whatever, then, it means to be united in Christ, it apparently does not change the basic social situation of master and slave (198)…. He does not, therefore, send Onesimus, the slave back to Philemon, the master; he sends one bother in Christ to another so that they can acknowledge each other as such (199).
It would be my contention that Thompson is wrong. It may be rather forcefully argued that Paul’s letter to the Philippians is similar in vein to Dio Chrysostom and that Paul himself was known to employ other forms of rhetoric as well (I would compare Paul’s letter to the Romans with Seneca’s Epistle 90, for starters); therefore, it would not be inconceivable that such a straightforward reading as Thompson is giving the Paul’s letter to Philemon would miss the finer details, the suggestion that Philemon free his slave as Paul through Christ freed Philemon. Further, I would argue that given the patrion-client relationship and the common theme as expressed in the letter of reciprocity (for example, 1.17-20; see MP 392), that Philemon would have had no choice not just to forgive Onesimus but to free him. Onesimus would serve as a token of obligation and perhaps even as a way for Philemon to publicly praise Paul.
Given the climate against the Christians, it would not behoove Paul to publically call for the overturning of such an ancient and recognized order such as Roman slavery. Yet, using the systems of classical rhetoric, and mimicking well known rhetoricians, Paul was calling for that exact thing, albeit in a way untraceable. Like Dio Chrysostom who didn’t urge for complete surrender of hope of self-rule but sought to show examples of how a city through morality may gain it, Paul simply suggested that Philemon remember what he owed Paul. What did he owe Paul but a debt which entailed preaching the good news?
In our modern setting, we are given the freedom of speech to shout what we want to. We like to pretend that the Church uses this to proclaim the prophetic voice, tying somehow freedom with the absolute fact of having to do something. In other words, many Christians would have the Church speak out on every moral vice or injustice simply because it can. Paul, like Pliny after him, was in a position to demand whatever he wanted, but that may have cost the Church the house of Philemon and a good friend. It wasn’t that Paul was sacrificing Onesimus on the altar of friendship, but using the escaped slave to test it and to lead others to the cause of Christ. We know by Church Tradition that Onesimus would later become an important bishop. Paul’s faith in Philemon and his own self-indulgent silence on calling for abolition and manumission vouchsafed the work of the Spirit to move, albeit slowly, in Onesimus’ life. Had Paul called for the outright end of slavery it would have brought down the might of Rome, more than it already had; or perhaps, just Onesimus’s manumission would have led to charges against Paul from others who already lying in wait for his errors. The Church, then, should follow Paul’s example and know when to speak or when to simply suggest, hoping that the tokens of friendship would be returned.
 Thompson, Marianne M. Colossians and Philemon (Two Horizons Commentary New Testament Commentary). Grand Rapids: Wm. B. Eerdmans , 2005. P196
 See 1.19, as well as v17. Compare with MP, 382, in which I would place Philemon as the client and Paul as the patron. Further. Paul now takes Onesimus as a kinsman further completely the picture of such a relationship. I would also suggest that Onesimus may sever as a toke of obligation between Paul and Philemon. See MP, 383).