Numbers 35:31-33

31Moreover, you shall accept no ransom for the life of a murderer, who is guilty of death, but he shall be put to death. 32And you shall accept no ransom for him who has fled to his city of refuge, that he may return to dwell in the land before the death of the high priest. 33You shall not apollute the land in which you live, for blood bpollutes the land, and no atonement can be made for the land for the blood that is shed in it, except cby the blood of the one who shed it.
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