10 Then Joshua turned back at that time, and captured Hazor and struck its king with the sword; for Hazor formerly was the head of all these kingdoms. 11 They struck every person who was in it with the edge of the sword, [e]utterly destroying them; there was no one left who breathed. And he burned Hazor with fire.12 Joshua captured all the cities of these kings, and all their kings, and he struck them with the edge of the sword, and utterly destroyed them; just as Moses the servant of the Lord had commanded. 13 However, Israel did not burn any cities that stood on their mounds, except Hazor alone, which Joshua burned. 14 All the spoil of these cities and the cattle, the sons of Israel took as their plunder; but they struck every man with the edge of the sword, until they had destroyed them. They left no one who breathed. 15 Just as the Lord had commanded Moses his servant, so Moses commanded Joshua, and so Joshua did; he left nothing undone of all that the Lord had commanded Moses.
16 Thus Joshua took all that land: the hill country and all the [f]Negev, all that land of Goshen, the lowland, the Arabah, the hill country of Israel and its lowland 17 from Mount Halak, that rises toward Seir, even as far as Baal-gad in the valley of Lebanon [g]at the foot of Mount Hermon. And he captured all their kings and struck them down and put them to death. 18 Joshua waged war a long time with all these kings. 19 There was not a city which made peace with the sons of Israel except the Hivites living in Gibeon; they took them all in battle. 20 For it was of the Lord to [h]harden their hearts, to meet Israel in battle in order that he might utterly destroy them, that they might [i]receive no mercy, but that he might destroy them, just as the Lord had commanded Moses.
21 Then Joshua came at that time and cut off the Anakim from the hill country, from Hebron, from Debir, from Anab and from all the hill country of Judah and from all the hill country of Israel. Joshua utterly destroyed them with their cities. 22 There were no Anakim left in the land of the sons of Israel; only in Gaza, in Gath, and in Ashdod some remained. 23 So Joshua took the whole land, according to all that the Lord had spoken to Moses, and Joshua gave it for an inheritance to Israel according to their divisions by their tribes. Thus the land had rest from war.
In a couple places in scripture, there’s an odd notation that God “hardened” someone’s heart. This seems like an strange thing, didn’t these people have free will? Well, of course they did, but obviously their hearts were inclined to hardness, or whatever God did wouldn’t have worked.
I don’t know all the ins and outs of that, nor do I understand fully how God could harden a heart. What I do know, is that it was part of His plan. Everything the Israelites were doing here was in following the command of God to conquer the land.
As they fought battle after battle, it must have seemed an interminable war. But the reality was that God had given them this land, and the only way that was going to happen was if they followed God’s plan. Sometimes, we don’t have such a clear directive. If we listen though, God will speak to our hearts, he will direct our path, and be a light on our way.