Leviticus 7:28-36

Then the LORD said to Moses, “Give the following instructions to the people of Israel. When you present a peace offering to the LORD, bring part of it as a gift to the LORD. Present it to the LORD with your own hands as a special gift to the LORD. Bring the fat of the animal, together with the breast, and lift up the breast as a special offering to the LORD. Then the priest will burn the fat on the altar, but the breast will belong to Aaron and his descendants. Give the right thigh of your peace offering to the priest as a gift. The right thigh must always be given to the priest who offers the blood and the fat of the peace offering. For I have reserved the breast of the special offering and the right thigh of the sacred offering for the priests. It is the permanent right of Aaron and his descendants to share in the peace offerings brought by the people of Israel. This is their rightful share. The special gifts presented to the LORD have been reserved for Aaron and his descendants from the time they were set apart to serve the LORD as priests. On the day they were anointed, the LORD commanded the Israelites to give these portions to the priests as their permanent share from generation to generation.”