Whose mouths must be stopped (ou dei epistomizein). Literally, "whom it is necessary to silence by stopping the mouth." Present active infinitive epistomizein, old and common verb (epi, stoma, mouth), here only in N.T. To stop the mouth either with bridle or muzzle or gag. Overthrow (anatrepousin). Old and common verb, to turn up, to overturn. In N.T. only here and 2 Timothy 2:18 . In papyri to upset a family by perversion of one member. Things which they ought not (a mh dei). Note subjective negative mh with indefinite relative and indicative mode. For filthy lucre's sake (aiscrou kerdou carin). The Cretans are given a bad reputation for itinerating prophets for profit by Polybius, Livy, Plutarch. Paul's warnings in 1 Timothy 3:31 Timothy 3:8 ; 1 Timothy 6:5 reveal it as "a besetting temptation of the professional teacher" (Parry). See verse Titus 1:7 above. Disgraceful gain, made in shameful ways.