A.T. Robertson Commentary Acts 5:7

"And it was about the space of three hours after, when his wife, not knowing what was done, came in." — Acts 5:7 (ASV)

And it was about the space of three hours after (εγενετο δε ως ωρων τριων διαστημα). Literally "Now there came an interval (διαστημα, distance, space between) of about (ως) three hours."

When (κα). This use of κα after εγενετο is characteristic of Luke's style in the Gospel.

Not knowing (μη ειδυια). Feminine singular of second perfect active participle of οιδα. Μη usual negative of the participle in the Koine.