Deuteronomy 19:7-9

Living Bible

^6-7 Anyone seeking to avenge the death will not be able to. These cities must be scattered so that one of them will be reasonably close to everyone; otherwise the angry avenger might catch and kill the innocent slayer, even though he should not have died since he had not killed deliberately.

⁸ “If the Lord enlarges your boundaries as he promised your ancestors, and gives you all the land he promised ⁹ (whether he does this depends on your obedience to all these commandments I am giving you today—loving the Lord your God and walking his paths), then you must designate three additional Cities of Refuge.