For I have derived much joy and comfort from your love, my brother, because the hearts of the saints have been refreshed through you.
Paul had to intercede for a young son in the faith with this short letter to Philemon. Thankfully, he was writing to a mature believer who was intimately connected in the fellowship of the Body of Christ. Philemon loved the church, ministered within the church, and had a reputation for refreshing the hearts of fellow Christians.
Paul appeals to this love that Philemon had for Christ and His church to help him do the same for Onesimus.Onesimus was Philemon's runaway slave. Somehow this slave made an escape, probably stealing from his master as he did so, and then fled to Rome. There, God in His sovereign mercy, put Onesimus in contact with Paul, and the gospel set him free! Now Paul urges Onesimus to return to his master, and for Philemon to forgive and receive Onesimus back into his household as a forgiven brother in Christ. It is a test of Philemon's commitment to the Body of Christ. It is a beautiful picture of just what the church is to be.
Because of the love Philemon had for all the saints, we see the culture of forgiveness already in his household. The gospel-shaped worldview of Philemon could love even a criminal who wronged him. It could extend grace to sinners, even trusted sinners who hurt him. It led him to forgive just as Christ forgives us. And this is how the gospel is truly refreshing!