A.T. Robertson Commentary John 8:27

"They perceived not that he spake to them of the Father." — John 8:27 (ASV)

They perceived not (ουκ εγνωσαν). Second aorist active indicative of γινωσκω. "Preoccupied as they were with thoughts of an earthly deliverer" (Westcott) and prejudiced against recognizing Jesus as the one sent from God.

That he spake to them of the Father (οτ τον πατερα αυτοις ελεγεν). Indirect assertion, but with the present indicative (λεγε) changed to the imperfect (ελεγεν) as was sometimes done (2:25) after a secondary tense.