Avenger of blood

(Heb. goel, from verb gaal, "to be near of kin," "to redeem"),
the nearest relative of a murdered person. It was his right and
duty to slay the murderer (2 Sam. 14:7, 11) if he found him
outside of a city of refuge. In order that this law might be
guarded against abuse, Moses appointed six cities of refuge (Ex.
21:13; Num. 35:13; Deut. 19:1,9). These were in different parts
of the country, and every facility was afforded the manslayer
that he might flee to the city that lay nearest him for safety.
Into the city of refuge the avenger durst not follow him. This
arrangement applied only to cases where the death was not
premeditated. The case had to be investigated by the authorities
of the city, and the wilful murderer was on no account to be
spared. He was regarded as an impure and polluted person, and
was delivered up to the "goel" (Deut. 19:11-13). If the offence
was merely manslaughter, then the fugitive must remain within
the city till the death of the high priest (Num. 35:25).