Now these are the nations which Yahweh left, to prove Israel by them, even as many [of Israel] as had not known all the wars of Canaan;
As Dalglish noted, "The nations of Canaan were left by Jehovah as a chastisement of Israel as well as a trial of their faith."[2]  The new situation brought about by Israel's disobedience also triggered the necessity for the nation to be schooled in the prosecution of wars which would inevitably follow their apostasy.