Joshua 20:2

cities of refuge "The cityes of fugityues," Wyclif. Prior to the Mosaic age, it was required of the nearest of kin, as a matter of duty, to avenge the death of a slain relative. He was called the Goelor Avenger, and together with his office inherited the property of the deceased. Sometimes a whole family took upon them this duty (2 Samuel 14:7). Among the Arab tribes of the present day, "any bloodshed whatever, whether wilful or accidental, laid the homicide open to the duteousrevenge of the relatives and family of the slain person, who again in their turn were then similarly watched and hunted by the opposite party, until a family war of extermination had legally settled itself from generation to generation, without the least prospect of a peaceful termination." It was the aim of the Mosaic Law, without altogether abolishing this long-established custom, to mitigate its evils as far as possible.

whereof I spake unto you The general directions on this subject will be found in (a) Exodus 21:13; (b) Numbers 35:9 ff.; (c) Deuteronomy 19:2. The reference to them here is one of the numerous instances in which the book of Joshua presupposes the existence of the Pentateuch.