useless wringlings -- KJV The word which is here used in the Received Text - παραδιατρίβη paradiatribē - occurs nowhere else in the New Testament. It properly means “mis-employment;” then “idle occupation.” (Robinson’s Lexicon)
The idea is that of employments that merely consumed time without any advantage.
constant friction ... -- Paul then spells out the result of the attitude and action of the false teachers: “envy” or “jealousy”; “strife” or “discord” (usually linked to envy); “malicious talk” or “slander” (blasfhmivai, blasphçmiai); “evil suspicions” or “conjectures”; and “constant friction” or “thorough or mutual irritation” which results “between men of corrupt [or ’ruined’] mind.” - CPNIV
Perverse -- useless
destitue [robbed] of the truth -- The perfect tense here for “have been robbed” indicates that these men were robbed of “the truth” in the past and are now reaping the consequence of that event.
Knight has suggested that the one doing the action conveyed by the passive verb, “have been robbed,” should be seen as “’the god of this world,’ [who] has brought about this condition.”
Gain -- a means for advancing. Using sacred work for secular gain. Supposing that the way to appear godly (to advance, get gain) is to argue, to cause war of words, and conditions of verse 4.
Since Paul warns against the quest for money governing a church leader’s life (1 Timothy 3:3, 1 Timothy 3:8; Titus 1:7, Titus 1:11) and argues that he himself does not minister in order to gain financially (1 Thessalonians 2:5), it is apparent that some have been using ministry or church leadership simply as a way to get ahead financially. - CPNIV
The thought here could be expressing the old Jewish belief that material prosperity was the evidence that God was pleased with the man and counted him righteous.
Withdraw thyself = "Timothy, don’t fall into a class of those men." A warning about "brotherhood camps", certain schools, and/or brotherhood publications that war on words, etc.