Ought (opeilomen). See for this word 1 John 2:6 ; 1 John 3:16 ; 1 John 4:11 . To welcome (upolambanein). Present active infinitive (habit of welcoming) of upolambanw, old word, to take up under, to carry off ( Acts 1:9 ), to reply ( Luke 10:30 ), to suppose ( Acts 2:15 ), only here in N.T. in this sense of receiving hospitably or to take under one's protection like upodecomai ( Luke 10:38 ). Such (tou toioutou). "The such" according to the Greek idiom ( 1 Corinthians 16:161 Corinthians 16:18 ). That we may be (ina ginwmeqa). Purpose clause with ina and the present middle subjunctive of ginomai, "that we may keep on becoming." Fellow-workers (sunergoi). Old compound (sun, ergon). With the truth (th alhqeiai). So associative instrumental case with sun in sunergoi, but it is not certain that this is the idea, though sunergew is so used with ergoi in James 2:22 . Sunergo itself occurs with the genitive of the person as in qeou sunergoi ( 1 Corinthians 3:9 ) or with genitive of the thing th cara ( 1 Corinthians 3:9 ). So then here the meaning may be either "co-workers with such brethren for the truth" (dative of advantage) or "co-workers with the truth" (associative instrumental case).