(4) They fled before the men of Ai.--A very natural reaction from overweening confidence to utter dismay is exhibited in this incident and its effect (Joshua 7:5), "the heart of the people melted and became as water." The demoralisation of Israel was a suitable penalty for their assumption, quite apart from its supernatural cause. It was absolutely necessary that the character of the conquest of Canaan should be vindicated, at whatever cost.

7:1-5 Achan took some of the spoil of Jericho. The love of the world is that root of bitterness, which of all others is most hardly rooted up. We should take heed of sin ourselves, lest by it many be defiled or disquieted, Heb 12:15; and take heed of having fellowship with sinners, lest we share their guilt. It concerns us to watch over one another to prevent sin, because others' sins may be to our damage. The easy conquest of Jericho excited contempt of the enemy, and a disposition to expect the Lord to do all for them without their using proper means. Thus men abuse the doctrines of Divine grace, and the promises of God, into excuses for their own sloth and self-indulgence. We are to work out our own salvation, though it is God that works in us. It was a dear victory to the Canaanites, whereby Israel was awakened and reformed, and reconciled to their God, and the people of Canaan hardened to their own ruin.So there went up thither of the people about three thousand men,.... Joshua detached from the army the largest number proposed, that there might be strength enough to take the place; and those he sent under proper officers to Ai, who went up to the very gate of the city, as appears from Joshua 7:5,

and they fled before the men of Ai; for upon their appearing at the gate of their city, they came out with all their forces against them, and as soon as they did, the children of Israel durst not face them, but without engaging with them fled at once: God having forsaken them, their courage failed, the dread of their enemies falling on them.