It is unclear exactly how Onesimus was useless to Philemon.1 Perhaps he was a lazy slave or his services were not really required. Most likely Paul is using wordplay with his name. Onesimus means useful in Greek. Now, with his newfound faith in Jesus Christ, Onesimus is proving to be a much better or more useful servant than what he was in the past.2
11 (Formerly he was useless to you, but now he is indeed useful to you and to me.)