Jamieson, Fausset & Brown

Salute Apelles approved--"the approved" in Christ--or, as we should say, "that tried Christian"; a noble commendation. Salute them which are of Aristobulus' household--It would seem, from what is said of Narcissus in Rom 16:11, that this Aristobulus himself had not been a Christian; but that the Christians of his household simply were meant; very possibly some of his slaves.