Leviticus 7:33

He among the sons of Aaron that offereth the blood of the peace offerings, and the fat,.... Who sprinkled the blood of them upon the altar round about, and burnt the fat upon it, which were rites enjoined to be observed, Leviticus 3:2:

shall have the right shoulder for [his] part; his particular part and share, because of his service: Aben Ezra remarks, that the right shoulder was given to him that sprinkled the blood, and the breast to all the priests; and Jarchi observes, that he that was fit for sprinkling the blood, and burning the fat, and went out an unclean person in the time of sprinkling the blood, or burning the fat, had no part in the flesh.