Deuteronomy 19:3-5

The Voice

^2-3 then designate three cities of refuge for yourselves in the land He is giving you to live in. Divide your territory into three parts, locate one city centrally in each part, and measure the roads to each of them. That way a person who kills someone accidentally can escape to one of these cities and be safe from revenge.

⁴ This is the kind of person I’m talking about: someone who kills a friend unintentionally, when there was no grudge between them, ⁵ such as when two friends go into the forest together to chop wood, and one of them swings an ax to cut a tree, and the ax head slips off the handle, hits his friend, and kills him. A person such as he can flee to one of these cities and be safe from revenge.