Deuteronomy 19:11-13

Cities of Refuge

¹¹But if any man hate his neighbor, and lie in wait for him, and rise up against him, and smite him mortally so that he dieth, and he flee into one of these cities; ¹²then the elders of his city shall send and fetch him thence, and deliver him into the hand of the avenger of blood, that he may die. ¹³Thine eye shall not pity him, but thou shalt put away the innocent blood from Israel, that it may go well with thee.

Laws of Landmark and Testimony