Leviticus 3:8 (KJV)

And if his offering for a sacrifice of peace offering unto the Lord be of the flock; male or female, he shall offer it without blemish.

If he offer a lamb for his offering, then shall he offer it before the Lord.

And 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.

And 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,

And the two kidneys, and the fat that is upon them, which is by the flanks, and the caul above the liver, with the kidneys, it shall he take away.