Leviticus 7:29-32

29“Tell the Israelites: The one who presents a fellowship sacrifice to the Lord is to bring an offering to the Lord from his sacrifice.

30His own hands will bring the food offerings to the Lord. He will bring the fat together with the breast. The breast is to be presented as a presentation offering before the Lord.

31The priest is to burn the fat on the altar, but the breast belongs to Aaron and his sons.

32You are to give the right thigh to the priest as a contribution from your fellowship sacrifices.