Deuteronomy 19:4-5

4 This is the rule concerning anyone who kills a person and flees there for safety—anyone who kills a neighbor unintentionally, without malice aforethought.
5 For instance, a man may go into the forest with his neighbor to cut wood, and as he swings his ax to fell a tree, the head may fly off and hit his neighbor and kill him. That man may flee to one of these cities and save his life.

Deuteronomy 19:4-5 Meaning and Commentary

INTRODUCTION TO DEUTERONOMY 19

This chapter contains an order to separate three cities of refuge in the land of Canaan, for such that killed a man unawares to flee to, of which those who were guilty of murder purposely were to have no benefit, De 19:1-13, a law is given against removing landmarks, De 19:14, and others concerning witnesses, that they should be more than one; be two, or three, De 19:15, and that a false witness, on conviction, should be punished, De 19:16-21.

Scripture quoted by permission.  Quotations designated (NIV) are from THE HOLY BIBLE: NEW INTERNATIONAL VERSION®.  NIV®.  Copyright © 1973, 1978, 1984, 2011 by Biblica.  All rights reserved worldwide.