Paul understands how to build strong relationships in community: by sharing words of gratitude and encouraging others. Paul is thankful for Philemon's character, faith in Christ, and love for the people of God.
It is a blessing to meet a true disciple of Christ. Unfortunately there are many who claim to be God's representatives but do more harm than good by blaspheming.
Philemon's love for the Christian community was able to refresh them. Selfless actions like this encouraged Paul. Philemon was also willingly hospitable and generous; offering his home as a place for worship and ministry to others. He was also a man of prayer.
Paul shows us that it is important to pray for those who are strong in the faith. Paul prays that Philemon will mentor other believers and show mercy on Onesimus (a former slave from Philemon's household who stole from Philemon and ran away). Onesimus has since become a Christian and Paul prays for Philemon to rise to the challenge of extending grace and forgiveness to others. (See 1 Samuel 25)