Verses 1-21
CONTENTS OF THE LETTER
Paul greets Philemon, his wife Apphia, and the other believers who meet in their home. He also greets Archippus, who was possibly their son and who was serving God in that region (1-3; cf. Colossians 4:17). Paul rejoices because of what he has heard (probably from Epaphras and Onesimus; cf. Colossians 1:7-8; Colossians 4:9; Colossians 4:12) of Philemon's strong faith in God and sincere love for God's people. This faith and love have been a source of strength and encouragement to the church in Colossae. Paul prays that Philemon will continue to share these blessings with others and so further build up the church (4-7).
Knowing Philemon's caring nature, Paul does not have to use his apostolic authority to command Philemon in any way. He knows he can depend on Philemon's generous spirit to forgive Onesimus and receive him back (8-9). Onesimus had once been a useless slave, but now his whole life has been changed. He has so lovingly helped Paul in prison that he has become like a son to Paul (10-11).
Although Paul would like to keep Onesimus with him, he feels that the right thing to do is to send him back to his original master, Philemon. No doubt Philemon would be happy to allow Onesimus to stay in Rome where he could continue to look after Paul, but that is a matter for Philemon to decide, not Paul. Whatever Philemon does, Paul wants him to do it willingly, not because Paul has forced him (12-14).
Perhaps it was God's will that Onesimus left Philemon briefly so that he might be saved eternally. No longer will he be a lazy and uncooperative slave, but a willing and helpful brother in Christ. Philemon should therefore treat him as a brother (15-16).
If Onesimus stole or damaged anything in making his escape, Paul will gladly pay the cost on Onesimus' behalf. However, Philemon should not forget the debt that he himself owes Paul, even his eternal salvation. But Paul's gladness will be much greater if Philemon freely forgives everything (17-20). Paul is confident that Philemon will act with generosity - maybe do even more than Paul suggests and give complete freedom to the slave (21).
Paul hopes to be released soon and pay a visit to Colossae. In the meantime, he and those with him send greetings to Philemon personally, in addition to the greetings they had sent to the whole church in the Colossian letter (22-25; cf. Colossians 4:10-14).