'Avenger of Blood' in the Bible

that the manslayer who kills any person accidentally or unintentionally may flee there. They shall be for you a refuge from the avenger of blood.

If the avenger of blood pursue after him, then they shall not deliver up the manslayer into his hand; because he struck his neighbor unintentionally, and did not hate him before.

These were the appointed cities for all the children of Israel, and for the stranger who sojourns among them, that whoever kills any person unintentionally might flee there, and not die by the hand of the avenger of blood, until he stands before the congregation.