The larger tribes of Israel must give more cities, and the smaller tribes must give fewer cities. Each tribe must give some of its cities to the Levites, but the number of cities they give will depend on the size of their land.”
When the Lord your God gives you land that belongs to the other nations, nations that he will destroy, you will force them out and live in their cities and houses.
This is the rule for someone who kills another person and runs to one of these cities in order to save his life. But the person must have killed a neighbor without meaning to, not out of hatred.