Leviticus 7:29-32

29“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.

30Present 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.

31Then the priest will burn the fat on the altar, but the breast will belong to Aaron and his descendants.

32Give the right thigh of your peace offering to the priest as a gift.