Deuteronomy 19:13

“Thine eye shall not pity him, etc.] This is not said to the avenger of blood, who is not to be supposed to have any pity or compassion on such a person, but to the elders, judges, and civil magistrates of the city to which he belonged, who took cognizance of his case; these were to show him no favour on account of his being a citizen, a neighbour, a relation or friend, or a rich man, or on any account whatever; but without favour or affection were to judge him and put him to death as a murderer; (see <043521> Numbers 35:21), but thou shall put away the guilt of innocent blood from Israel; by which they would be defiled, and be liable to punishment for it; (see <043533>Numbers 35:33,34), the…”

“This and the next two chapters contain enactments designed to protect human life, and to impress its sanctity on Israel. In Deuteronomy 19:1-13 the directions respecting the preparation of the roads to the cities of refuge, the provision of additional cities in case of an extension of territory, and the intervention of the elders as representing the congregation, are unique to Deuteronomy and supplementary to the laws on the same subject given in the earlier books (compare the marginal reference). Deuteronomy 19:1, Deuteronomy 19:2 The three cities of refuge for the district east of Jordan had been already named. Moses now directs that when the territory on the west of Jordan had been…”

“19:13 Purge (literally burn): The only way for the land to be free of culpability in matters of homicide was for blood vengeance to be enacted, which would burn out the impurity. See also 13:5; 17:12.”

“Thine eye: Deu 7:16, Deu 13:8, Deu 25:12; Eze 16:5 but thou: Deu 21:9; Gen 9:6; Lev 24:17, Lev 24:21; Num 35:33, Num 35:34; Sa2 21:1, Sa2 21:14; Kg1 2:31 Deuteronomy 19:14”