Abstract After an introduction to the letter to Philemon this article argues that the traditional identification of Onesimus as the letter carrier is far more plausible than any of the recently proposed alternatives (Tychicus, Timothy, an unknown person). It is further argued that the letter addresses the relationships between Paul, Philemon, and Onesimus, using language reminiscent of the ‘letter of recommendation’. Since such letters are both habitually ambiguous and require the letter carrier to continue the conversation initiated by the letter, it follows that Onesimus was trusted by Paul to help Philemon receive the letter. It is further argued on both general and Pauline grounds that it is plausible to think that Onesimus would have resolved the ambiguity inherent in the written communication with a verbal request for manumission.