20 The men of Ai looked back and saw the smoke of the city rising up into the sky, but they had no chance to escape in any direction; the Israelites who had been fleeing toward the wilderness had turned back against their pursuers.

Matthew Henry's Commentary on Joshua 8:20

Commentary on Joshua 8:3-22

(Read Joshua 8:3-22)

Observe Joshua's conduct and prudence. Those that would maintain their spiritual conflicts must not love their ease. Probably he went into the valley alone, to pray to God for a blessing, and he did not seek in vain. He never drew back till the work was done. Those that have stretched out their hands against their spiritual enemies, must never draw them back.