A.T. Robertson Commentary Matthew 24:43

"But know this, that if the master of the house had known in what watch the thief was coming, he would have watched, and would not have suffered his house to be broken through." — Matthew 24:43 (ASV)

In what watch (ποια φυλακη). As in 14:25 (four watches of the night).

Broken through (διορυχθηνα). Digged through the tile roof or under the floor (dirt in the poorer houses).