A.T. Robertson Commentary 1 Corinthians 12:2

"Ye know that when ye were Gentiles [ye were] led away unto those dumb idols, howsoever ye might led." — 1 Corinthians 12:2 (ASV)

Ye were led away (απαγομενο). The copula ητε is not expressed (common ellipsis) with the participle (periphrastic imperfect passive), but it has to be supplied to make sense. Some scholars would change οτε (when) to ποτε (once) and so remove the difficulty.

Unto those dumb idols (προς τα ειδωλα τα αφωνα). "Unto the idols the dumb." See Ps 95:5-7 for the voicelessness (α-φωνα, old adjective, without voice, φωνη) of the idols. Pagans were led astray by demons (1 Corinthians 10:19f.).

Howsoever ye might be led (ως αν ηγεσθε). Rather, "as often as ye were led." For this use of ως αν for the notion of repetition, regular Koine idiom, see Robertson, Grammar, p. 974. Cf. οπου αν in Mr 6:56.