Exodus 29:22-28

22“Take from this ram the fat, the fat tail, the fat on the internal organs, the long lobe of the liver, both kidneys with the fat on them, and the right thigh. (This is the ram for the ordination.) 23From the basket of bread made without yeast, which is before the LORD, take one round loaf, one thick loaf with olive oil mixed in, and one thin loaf. 24Put all these in the hands of Aaron and his sons and have them wave them before the LORD as a wave offering. 25Then take them from their hands and burn them on the altar along with the burnt offering for a pleasing aroma to the LORD, a food offering presented to the LORD .

26After you take the breast of the ram for Aaron’s ordination, wave it before the LORD as a wave offering, and it will be your share. 27“Consecrate those parts of the ordination ram that belong to Aaron and his sons: the breast that was waved and the thigh that was presented.

28This is always to be the perpetual share from the Israelites for Aaron and his sons. It is the contribution the Israelites are to make to the LORD from their fellowship offerings.