Deuteronomy 4:42

Someone could flee there who committed manslaughter, killing his neighbor accidentally without previously hating him. He could flee to one of these cities and stay alive:

Numbers 35:6

“The cities you give the Levites will include six cities of refuge, which you must provide so that the one who kills someone may flee there; in addition to these, give 42 other cities.

Numbers 35:11-12

designate cities to serve as cities of refuge for you, so that a person who kills someone unintentionally may flee there.

Numbers 35:15-28

These six cities will serve as a refuge for the Israelites and for the foreigner or temporary resident among them, so that anyone who kills a person unintentionally may flee there.

Deuteronomy 19:1-10

“When the Lord your God annihilates the nations whose land He is giving you, so that you drive them out and live in their cities and houses,

Hebrews 6:18

so that through two unchangeable things, in which it is impossible for God to lie, we who have fled for refuge might have strong encouragement to seize the hope set before us.

Treasury of Scripture Knowledge

Summary

That the slayer might flee thither, which should kill his neighbour unawares, and hated him not in times past; and that fleeing unto one of these cities he might live:

Bible References

General references

Deuteronomy 19:1
“When the Lord your God annihilates the nations whose land He is giving you, so that you drive them out and live in their cities and houses,
Numbers 35:6
“The cities you give the Levites will include six cities of refuge, which you must provide so that the one who kills someone may flee there; in addition to these, give 42 other cities.
Hebrews 6:18
so that through two unchangeable things, in which it is impossible for God to lie, we who have fled for refuge might have strong encouragement to seize the hope set before us.

Holman Christian Standard Bible®, Copyright © 1999, 2000, 2002, 2003, 2009 by Holman Bible Publishers.