'Avenger of Blood' in the Bible

that the manslayer who kills any person unintentionally, without premeditation, may flee there, and they shall become your refuge from the avenger of blood.

Now if the avenger of blood pursues him, then they shall not deliver the manslayer into his hand, because he struck his neighbor without premeditation and did not hate him beforehand.

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