Joshua 11:18-20

18Joshua waged war a long time with all these kings. 19There was not a city which made peace with the sons of Israel except 1the Hivites living in Gibeon; they took them all in battle. 202For it was of the Lord to 3harden their hearts, to meet Israel in battle in order that he might 4utterly destroy them, that they might 5receive no mercy, but that he might destroy them, just as the Lord had commanded Moses.