Leviticus 7:29-32

29‘Say to Israel's people, “When a person gives an animal as a friendship offering, he must bring part of it to the Lord.

30He must carry the offering in his own hands to the fire. He must bring the fat and the meat of the ribs and he must lift the meat to the Lord.

31The priest will burn the fat at the altar. He will lift the meat of the ribs to God. Then Aaron's sons can eat it.

32The top part of the back right leg of the animal is a gift.