Deuteronomy 19:11-13

11“But if anyone hates his neighbor and lies in wait for him and attacks him aand strikes him fatally so that he dies, and he flees into one of these cities, 12then the elders of his city shall send and take him from there, and hand him over to the avenger of blood, so that he may die. 13 bYour eye shall not pity him, cbut you shall purge the guilt of innocent blood
Or  the blood of the innocent
from Israel, so that it may be well with you.

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