14. at a time appointed--either an hour concocted between the king and people of Ai and those of Beth-el, who were confederates in this enterprise, or perhaps they had fixed on the same time of day, as they had fought successfully against Israel on the former occasion, deeming it a lucky hour (Jud 20:38).
      but he wist not that there were liers in ambush against him behind the city--It is evident that this king and his subjects were little experienced in war; otherwise they would have sent out scouts to reconnoitre the neighborhood; at all events, they would not have left their town wholly unprotected and open. Perhaps an ambuscade may have been a war stratagem hitherto unknown in that country, and among that people.

JFB.