As Isaiah preaches, he forthrightly declares what God will not do; it is a petition stated in a declarative way: “Therefore, do not forgive them!” The NET reads, “Don’t spare them!”
Israel (man), in all his wisdom, is going to be humbled and the Lord will be exalted! It was man’s pride that brought all these vices into the land of Israel and corrupted it (and them). Can man hide from God? Not a chance! There is not a place man can know or go that God doesn’t know or is already there. But, with man’s inclination of self-preservation, he seeks to hide in the rocks from the terror of the Lord; as he exalts himself the only real result will be haughtiness humbled.