When Joshua and all Israel saw that the men in ambush had captured the city and that smoke was rising from it, they turned around and struck down the men of Ai.
We have here an account of the taking of Ai by stratagem. The stratagem here used, we are sure, was lawful and good; God himself appointed it, and we have no reason to think but that the like is lawful and good in other wars.
Commenting on Joshua 8:3-22
And when Joshua,.... Or "for Joshua" (z): and all Israel saw that the ambush had taken the city; which they knew by the smoke, as follows: and that the smoke of the city ascended; in large columns, which sufficiently indicated that the whole city was taken and fired by the ambush: then, or, "and": they turned again and slew the men of Ai; great numbers of them.
Jos 8:14-23 When the king of Ai saw the Israelites, he hurried out in the morning against them to battle at the (previously) appointed place (למּועד, in locum condictum, as in 1Sa 20:35) before the steppe (Arabah, not the valley of the Jordan, but the steppe or desert of Bethaven; see at Jos 7:2), as he knew nothing of the ambuscade behind the town.
Commenting on Joshua 8:14-23