A.T. Robertson Commentary Acts 23:28

"And desiring to know the cause wherefore they accused him, I brought him down unto their council:" — Acts 23:28 (ASV)

To know (επιγνωνα). To know fully, επ, second aorist active infinitive.

They accused him (ενεκαλουν αυτω). Imperfect active indicative, were accusing him (dative), repeating their charges.