What does Philemon 1:11 mean?

According to Paul, Onesimus had been useless to Philemon, as a runaway, but was now useful to both Philemon and Paul. The Greek term for "useless" is archreston, which rhymes with euchreston, meaning "useful." These rhymes also make a play on words, based around the meaning of Onesimus' name: "useful."

Interestingly, Paul mentions "useful" twice in his letter to 2 Timothy. First, he used the spiritual analogy of a person's value to the master of the house (2 Timothy 2:21). Second, this same term for usefulness or value is applied to Mark, who served with Paul on a mission trip and wrote the Gospel of Mark. Paul told Timothy to bring Mark along on account of this usefulness in ministry (2 Timothy 4:11).

Onesimus is now useful both to Paul and to Philemon. Onesimus had been helpful to Paul in his imprisonment, by delivering the letter to the Colossian church and this letter to Philemon. He may have assisted Paul in other ways as well. Onesimus obviously could have been useful to Philemon as a slave, but would now be more useful since he was a fellow believer. In the next verses, Paul makes a request of Philemon to make Onesimus even more useful—expecting him to be forgiven, freed, and able to serve in ministry.