Leviticus 7:29-32

²⁹Say to the children of Israel: He who makes a peace-offering to the Lord, is to give an offering to the Lord out of his peace-offering:

³⁰He himself is to take to the Lord the offering made by fire, even the fat with the breast, so that the breast may be waved for a wave offering before the Lord.

³¹And the fat is to be burned by the priest on the altar, but the breast is for Aaron and his sons.

³²And the right leg you are to give to the priest for an offering to be lifted up out of what is given for your peace-offerings.