Greet Amplias (or, Ampliatus) my beloved in the Lord. Salute Urban (i.e. Urbanus) our fellow-worker in Christ, and Stachys my beloved. Salute Apellos approved in Christ. Salute them which are of Aristobulus' household.
As to who Aristobulus might be (viz. a grandson of Herod the Great, mentioned by Josephus, 'Ant.,' 20. l, 2, as being at Rome in a private station), see Lightfoot on 'Philippians,' p. 172, and 'Dict.
of Gr. and Romans Biog.,' under "Aristobulus," 5. "Those of Aristobulus" ( τῶν αριστοβούλου) would probably be his familia of slaves (cf. τῶν χλόης, 1 Corinthians 1:11, and below, τῶν ναρκίσσου).
The salutation is not to the whole household, but to the Christians among them, as intimated by τοὺς ἐκ τῶν, and more definitely expressed below in the ease of the household of Narcissus.