How did the Canaanites respond to God's patience?
Rather than repenting during the centuries God patiently waited, the Canaanites refused to turn from their iniquity. They moved deeper into wickedness, immorality, and abominations, until their corruption reached the point that God instructed Joshua and Israel to spare none of them and cleanse the land.
Les explains that God waited roughly four hundred and ninety years, from Abraham’s call until Joshua led Israel in, for the Canaanites to turn from their iniquity. Instead, they did not turn; they went deeper and deeper into wickedness, immorality, and abominations. Eventually God could tell Joshua to instruct Israel not to spare a one of them, because the land needed total cleansing. Les uses the illustration of a rotten potato or apple: if a half-rotten one is placed among good ones, soon the whole group becomes rotten. That is the lesson God was teaching Israel: remove the rot, or it will infect and destroy you, and then God would have to deal with you. Les notes this is exactly what happened.