Leviticus 4:30

30And the priest shall take some of its blood with his finger and put it on the horns of the altar of burnt offering and pour out all the rest of its blood at the base of the altar.

Leviticus 17:11

11 aFor the life of the flesh is in the blood, and I have given it for you on the altar bto make atonement for your souls, cfor it is the blood that makes atonement by the life.
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