1“‘If his offering is a sacrifice of peace offerings, if he offers it from the herd, whether male or female, he shall offer it without defect before Yahweh. 2He shall lay his hand on the head of his offering, and kill it at the door of the Tent of Meeting. Aaron’s sons, the priests, shall sprinkle the blood around on the altar. 3He shall offer of the sacrifice of peace offerings an offering made by fire to Yahweh. The fat that covers the innards, and all the fat that is on the innards, 4and the two kidneys, and the fat that is on them, which is by the loins, and the cover on the liver, with the kidneys, he shall take away. 5Aaron’s sons shall burn it on the altar on the burnt offering, which is on the wood that is on the fire: it is an offering made by fire, of a pleasant aroma to Yahweh.
6“‘If his offering for a sacrifice of peace offerings to Yahweh is from the flock, either male or female, he shall offer it without defect. 7If he offers a lamb for his offering, then he shall offer it before Yahweh; 8and he shall lay his hand on the head of his offering, and kill it before the Tent of Meeting. Aaron’s sons shall sprinkle its blood around on the altar. 9He shall offer from the sacrifice of peace offerings an offering made by fire to Yahweh; its fat, the entire tail fat, he shall take away close to the backbone; and the fat that covers the entrails, and all the fat that is on the entrails, 10and the two kidneys, and the fat that is on them, which is by the loins, and the cover on the liver, with the kidneys, he shall take away. 11The priest shall burn it on the altar: it is the food of the offering made by fire to Yahweh.
12“‘If his offering is a goat, then he shall offer it before Yahweh. 13He shall lay his hand on its head, and kill it before the Tent of Meeting; and the sons of Aaron shall sprinkle its blood around on the altar. 14He shall offer from it as his offering, an offering made by fire to Yahweh; the fat that covers the innards, and all the fat that is on the innards, 15and the two kidneys, and the fat that is on them, which is by the loins, and the cover on the liver, with the kidneys, he shall take away. 16The priest shall burn them on the altar: it is the food of the offering made by fire, for a pleasant aroma; all the fat is Yahweh’s.
17“‘It shall be a perpetual statute throughout your generations in all your dwellings, that you shall eat neither fat nor blood.’”
Aaron was the son of Amram and Jochebed, the brother of Moses and Miriam, and the first priest of Israel. God appointed Aaron to be Moses' spokesman in his audiences with the unnamed Pharaoh of Exodus. As a symbol of his office, Aaron received a magical rod. He turned the rod into a snake - the first in a series of signs, by which he and Moses hoped to persuade Pharaoh to let the Israelites leave Egypt. Aaron also used the rod to call down three of the plagues that followed this first sign (polluting the Nile, frogs and gnats). God also caused the rod to blossom and bear ripe almonds, as a sign that Aaron's descendants would inherit the priesthood.
God summoned Aaron to be present when Moses received the Ten Commandments. But Aaron did not stay on Sinai. Instead he agreed to oversee the casting of an idol (a golden calf) for the Israelites who had rebelled against the authority of the absent Moses.
Aaron was generally a supporter of Moses, but took him to task for his marrying a Cushite wife. For this God rebuked Aaron (and Miriam). His role as priest was critical when he made atonement for the Israelites and stayed the plague that had followed the rebellion of Dathan and Abiram. Exodus and Leviticus give a detailed account of the vestments and duties of Aaron and of his sons.
Aaron's elder sons, Nadab and Abihu, died early but the younger pair, Eleazar and Ithamar, succeeded him in the priesthood. When Aaron was a hundred and twenty three, God instructed him to go up onto Mt. Hor, where he died. Aaron figures prominently in Exodus, Leviticus, Deuteronomy and Numbers, and is named in other books of both Old and New Testaments.