A.T. Robertson Commentary 1 Timothy 1:6

"from which things some having swerved have turned aside unto vain talking;" — 1 Timothy 1:6 (ASV)

Having swerved (αστοχησαντες). First aorist active participle of αστοχεω, compound

Koine verb (Polybius, Plutarch) from αστοχος (α privative and στοχος, a mark), "having missed the mark." In N.T. only here, 6:21; 2 Timothy 2:18. With the ablative case ων (which).

Have turned aside (εξετραπησαν). Second aorist passive indicative of εκτρεπω, old and common verb, to turn or twist out or aside. In medical sense in Heb 12:13. As metaphor in 1 Timothy 1:6; 6:20; 2 Timothy 4:4.

Vain talking (ματαιολογιαν). Late word from ματαιολογος, only here in N.T., in the literary Koine.