Numbers 35:9-34

So if Israel failed to keep the land from being polluted, the implication of Numbers 35:34 is that God would no longer be with His people in the land and that Israel would no longer be successful in the land, meaning it would not produce the bumper crops that God blesses it with. We have seen bumper crops for decades, if not centuries, in this nation and now they are starting to have more and more problems with fires and drought and so on. God warned of this many, many times in Scripture, but they do not read Scripture, so they do not know, so history repeats itself.

The cities of refuge were therefore a provision to enable Israel to keep the land. Without such a place the avenger of blood would hunt the person down and kill the accused without any determination of guilt or innocence, which would pollute the land. Though if the accused was innocent and killed by the avenger of blood, this would pollute the land and lead to the loss of the land. And this system was thus part of the Lord's gracious provision that enabled a sinful people to live with a holy God.