The Epistle of Paul the Apostle to Philemon is a personal letter in which the apostle beseeches Philemon to take back a runaway slave, Onesimus. The slave had come to Rome, where Paul was being held prisoner, and there had been converted by Paul.

Philemon 1

1:21 Having confidence in thy obedience I wrote unto thee, knowing that thou wilt also do more than I say.