Philemon

It is the shortest letter of Paul.  Paul wrote this personal letter to Philemon, a rich believer in Colossae.  In this letter, Paul only tried to resolve one issue, which happened to be a common social phenomena at that time - the issue of slavery. 

Philemon had a slave who escaped after stealing.  The slave came to Paul for protection.  However, Paul encouraged the slave to go back to his master in Colossae with the letter.  In his letter, Paul asked for the master’s forgiveness to the slave because he was now a brother in Christ.  In Roman times, the owner had the right to kill any escaped slave.  The way how Paul handled the issue was provocative in that era.