Leviticus 3:8-9

⁸And he shall lay his hand upon the head of his offering, and kill it before the tabernacle of the congregation: and Aaron’s sons shall sprinkle the blood thereof round about upon the altar.

⁹And he shall offer of the sacrifice of the peace offering an offering made by fire unto the LORD; the fat thereof, and the whole rump, it shall he take off hard by the backbone; and the fat that covereth the inwards, and all the fat that is upon the inwards,