Numbers 35:12

12The cities shall be for you a refuge from the avenger, that the manslayer may not die until he stands before the congregation for judgment.

Numbers 35:30

30“If anyone kills a person, the murderer shall be put to death on the aevidence of witnesses. But no person shall be put to death on the testimony of one witness.

Deuteronomy 19:12

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.
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