As Israel entered Canaan they experienced an awesome and total victory over the city of Jericho. It is striking then to have this victory so quickly followed by humiliating defeat at Ai. God took His hand of favor off of Israel allowing them to be defeated because "they acted unfaithfully in regard to the devoted things." One man, Achan, saw, coveted and took a bit of plunder. This sin had a sudden consequence.
How important is avoiding sin and its consequences today... particularly when it comes to covetousness? Very important!