Jamieson, Fausset and Brown on 1 Timothy 6:5

5. Perverse disputings--useless disputings. The oldest manuscripts read, "lasting contests" [Wiesinger]; "incessant collisions" [Alford]. "Strifes of words" had already been mentioned so that he would not be likely to repeat the same idea (as in the English Version reading) again.

corrupt minds--Greek, "of men corrupted (depraved) in mind." The inmost source of the evil is in the perverted mind (1Ti 6:4; 2Ti 3:8; Tit 1:15).

destitute of the truth--(Tit 1:14). They had had the truth, but through want of moral integrity and of love of the truth, they were misled by a pretended deeper gnosis (knowledge) and higher ascetical holiness, of which they made a trade [Wiesinger].

supposing, &c.--The Greek requires, "supposing (regarding the matter in this point of view) that piety (so translated for 'godliness') is a means of gain (that is, a way of advancing one's worldly interests: a different Greek form, poriswa, expresses the thing gained, gain)"; not "that gain is godliness," as English Version.

from such withdraw thyself--omitted in the oldest manuscripts. The connection with 1Ti 6:6 favors the omission of these words, which interrupt the connection.