Titus 1:11

οὓς δεῖ ἐπιστομίζειν : quos oportet redargui, whose mouths must be stopped by the unanswerable arguments of the orthodox controversialist. This is the result hoped for from the “conviction,” of Titus 1:9.

ὅλους οἴκους ἀνατρέπουσιν : pervert whole families (Alf.); Moulton and Milligan give an apt illustration from a papyrus of second cent. B.C., τῆς πατρικῆς οἰκίας … ἔτι ἔνπροσθεν ἄρδην [ἀ] νατετραμμένης διʼ ἀσ [ω] τίας (Expositor, vii., 1:269). This suggests the rendering upset. The whole family would be upset by the perversion of one member of it.

ἃ μὴ δεῖ : Normally, οὐ is used in relative sentences with the indicative. Other exceptions will be found in 2Pe 1:9, 1 John 4:3 (T.R.). It is possible that the force of μή here is given by translating, which (we think) they ought not. If the teaching had been absolutely indefensible by any one, he would have said, ἃ οὐ δεῖ. See Blass, Grammar, p. 254.

αἰσχροῦ κέρδους χάριν : The three reff. on αἰσχροῦ, the only other occurrences in N.T. of this adj., are instances of the phrase αἰσχρόν ἐστι. The reference is to the claim to support made by itinerating or vagrant prophets and apostles such as are referred to in the Didache, cc. 11, 12, and alluded to in 2 Corinthians 11:9-13. All such abuses would exist in an aggravated form in Crete, the natives of which had an evil reputation for αἰσχροκέρδεια, according to Polybius, ὥστε παρὰ μόνοις Κρηταιεῦσι τῶν ἁπάντων ἀνθρώπων μηδέν αἰσχρὸν νομίζεσθαι κέρδος. (Hist. vi. 46. 3, cited by Ell.). They get a bad character also from Livy (xliv. 45), and Plutarch (Paul. Aemil. 23). The Cretans, Cappadocians, and Cilicians were τρία κάππα κάκιστα.