Exodus 29:26-28

After 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. “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. This 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.