John Dummelow's Commentary on the Bible - Joshua 8:1-35
The Conquest of Ai. The Covenant confirmed upon Mt. Ebal1-29. The Taking of Ai. Edersheim explains that Joshua detailed a corps of 30,000 men, of whom 5,000 were placed W. of Ai in a wood. The 25,000 pitched K of Ai, and subsequently moved forward into the valley below the city. Then came the feigned attack and retreat eastward, the signal from Joshua, and the assault by the ambush from the rear. It should be noted, however, that there are two accounts of the ambush, one in Joshua 8:3, Joshua... read more
Expository Notes of Dr. Thomas Constable - Joshua 8:3-13
Out of the 40,000 Israelite soldiers, Joshua chose 30,000 for this battle. Of these he sent 5,000 to hide in ambush west of the town. The remaining 25,000 (double the population of Ai, Joshua 8:25) approached Ai from the north. "Took" (Joshua 8:12) makes better sense if read "had taken." read more