Whom I would have retained with me,.... At Rome, where the apostle was a prisoner:that in thy stead he might have ministered unto me in the bonds of the Gospel; the apostle was in bonds, not for any crime, for any immorality he had been guilty of, but for the sake of the Gospel, for professing and preaching that; for this he was an ambassador in bonds, as he elsewhere says, Eph 6:20.
Now he would have kept Onesimus with him, either to have waited upon him, in his bonds, and to have provided for him the necessaries of life; or to have assisted him in the ministration of the word, in the room of Philemon, who, had he been there, would have been employed in such service; so that if the apostle had retained him, he would have been acting not for himself, but in the room of his master, and doing what he should have done, had he been on the spot.
This the apostle observes to prevent an objection that might have been made; that since Onesimus was become so profitable to him, why did he send him back? why did he not keep him for his own service?