Deuteronomy 19:2-13

2Thou shalt set apart three cities for thee in the midst of thy land, which the LORD thy God giveth thee to possess it. 3Thou shalt prepare thee a way, and divide the bounds of thy land, which the LORD thy God giveth thee to inherit, into three parts, that every slayer may flee there. 4And this is the case of the slayer, who shall flee there, that he may live: Whoever killeth his neighbour unintentionally, whom he hated not in time past;1 5As when a man goeth into the forest with his neighbour to hew wood, and his hand maketh a stroke with the axe to cut down the tree, and the head slippeth from the helve, and falleth upon his neighbour, that he dieth; he shall flee to one of these cities, and live:234 6Lest the avenger of blood shall pursue the slayer, while his heart is hot, and overtake him, because the way is long, and slay him; though he was not worthy of death, inasmuch as he hated him not in time past.56 7Therefore I command thee, saying, Thou shalt set apart three cities for thee. 8And if the LORD thy God shall enlarge thy land, as he hath sworn to thy fathers, and give thee all the land which he promised to give to thy fathers; 9If thou shalt keep all these commandments to do them, which I command thee this day, to love the LORD thy God, and to walk ever in his ways; then shalt thou add three cities more for thee, besides these three: 10That innocent blood may not be shed in thy land, which the LORD thy God giveth thee for an inheritance, and so blood be upon thee. 11But if any man shall hate his neighbour, and lie in wait for him, and rise up against him, and smite him mortally that he dieth, and he shall flee into one of these cities:7 12Then the elders of his city shall send and bring him from there, and deliver him into the hand of the avenger of blood, that he may die. 13Thy eye shall not pity him, but thou shall remove the guilt of innocent blood from Israel, that it may be well with thee.