Philemon: Only 1 Chapter
Philemon was probably a wealthy, Christian man that had slaves and Onesimus was one of them. For whatever reason, Onesimus ran away from Philemon which was a wrong thing to do. The slave ended up in Rome and responds favorably to the Gospel that Paul preached while in prison. Paul quickly bonded well with Onesimus and writes to Philemon informing him that he is sending his slave back to him as a changed man. Instead of his former unsaved state (useless) he is now useful (which is what his name means) as a fellow believer. Paul has so much confidence in Onesimus that he tells Philemon that if Onesimus does anything wrong he would cover it. It is always nice to have someone put that much confidence in us.
Overall, this underscores the truth and power of grace. Both the Roman Law and the Mosiac Law condemned Onesimus to death, but Christ’s mercy and grace not only saved Onesimus’ life but changed his inner self for the better. This is exactly what Christ does for sinners.
This may be a stretch, but Philemon may represent the Heavenly Father, Paul may be Jesus, and Onesimus may be you and I as sinners rebelling and running away from God. Paul (Jesus) restores the broken relationship and sends back Onesimus to be with his former master Philemon covering anything Onesimus might do wrong in the future.