8:3 To go up against Ai - That is, to consider about this expedition; not as if all the people of war did actually go up, which was both unnecessary and burdensome: but it seems to be resolved by Joshua and all the council of war, that the thirty thousand here following should be selected for the enterprize. Either, 1, the thirty thousand now mentioned; or,
2. part of them; namely, such as were to lie in wait; and these were only five thousand men, as is expressed, ver.12.
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.