10 For there are many insubordinate, both idle talkers and deceivers, especially those of the circumcision,
11 whose mouths must be stopped, who subvert whole households, teaching things which they ought not, for the sake of dishonest gain.
insubordinate (v.10) = cannot be subjected to control — the same word used of children in verse 6 (1 Timothy 1:9)
idle talkers (v.10) = ones who utter empty, senseless things — devoid of force, truth, success, result
deceivers (v.10) = mind deceivers
especially (v.10) — the deceivers may not all have been Judaizers, but most of them, and certainly the most destructive among them, were
those of the circumcision (v.10) — Judaizers
The persons spoke of here were Christian Jews … that they were at least nominally Christians is also implied by the epithet “unruly” [insubordinate]. We cannot call those persons unruly on whose obedience we have no claim. — Wuest, page 186
Those of “the circumcision,” at least many of them, were doubtless present at Pentecost, where some are mentioned as having come from Crete (Acts 2:5, 11), but it appears that upon their return to Crete they had not even continued faithfully in the doctrine of the twelve, but had reverted to apostate Judaism with its Talmud and all its civil and religious laws — laws which seemed to excel even the Ten Commandments in righteousness, but which in reality condemned many practices which were wholly right and pure (v.14: cf., Matthew 15:1-8). — Stam, pages 253-254.
mouths must be stopped (v.11) = bridled
“To stop the mouth” is epistomizo, originally “to put something into the mouth,” as a bit into a horse’s mouth. The noun form is used of the “stop” of a waterpipe. The verb used metaphorically means “to reduce to silence.” [So] … “whom it is necessary to silence.” — Wuest, page 186.
subvert (v.11) = overthrow, overturn, destroy — used in John 2:15 of overthrowing tables, in 2 Timothy 2:18 of overthrowing the faith
households (v.11) = families
for the sake of dishonest gain (v.11) — Itinerants or vagrants who claimed to be prophets or apostles made claims for financial support.