3. What an infatuated enemy the king of Ai was, (1.) That he did not by his scouts discover those that lay in ambush behind the city, v. 14. Some observe it as a remarkable instance of the power of God in making men blind to their own interest, and the things that belong to their peace, that he wist not that there were liers in wait against him. Those are most in danger who are least aware that they are so. (2.) That when Israel seemed to fly he drew out all his forces to pursue them, and left none to guard his city and to secure his retreat, v. 17. Thus the church's enemies often run themselves into destruction by their own fury and the violence of their rage against the Israel of God. Pharaoh plunged himself into the Red Sea by the eagerness with which he pursued Israel. (3.) That from the killing of thirty-six men out of 3000, when Israel made the former attack upon his city, he should infer the total routing of so great an army as now he had to deal with (v. 6): They flee before us as at the first. See how the prosperity of fools destroys them and hardens them to their ruin. God had made use of the men of Ai as a scourge to chastise his people for meddling with the accursed thing, and this had puffed them up with a conceit that they must have the honour of delivering their country from these formidable invaders; but they were soon made to see their mistake, and that when the Israelites had reconciled themselves to their God they could have no power against them. God had made use of them only for the rebuking of Israel, with a purpose, when the correction was over, to throw the rod itself into the fire; howbeit, they meant not so, but it was in their heart to destroy and cut off, Isa. x. 5-7.