Duties of Priests and Levites 1
Then the LORD said to Aaron: "You, your sons, and your relatives from the tribe of Levi will be held responsible for any offenses related to the sanctuary. But you and your sons alone will be held responsible for violations connected with the priesthood.
"Bring your relatives of the tribe of Levi—your ancestral tribe—to assist you and your sons as you perform the sacred duties in front of the Tabernacle of the Covenant. 
But as the Levites go about all their assigned duties at the Tabernacle, they must be careful not to go near any of the sacred objects or the altar. If they do, both you and they will die.
The Levites must join you in fulfilling their responsibilities for the care and maintenance of the Tabernacle, 
but no unauthorized person may assist you.
"You yourselves must perform the sacred duties inside the sanctuary and at the altar. If you follow these instructions, the LORD's anger will never again blaze against the people of Israel.
I myself have chosen your fellow Levites from among the Israelites to be your special assistants. They are a gift to you, dedicated to the LORD for service in the Tabernacle.
But you and your sons, the priests, must personally handle all the priestly rituals associated with the altar and with everything behind the inner curtain. I am giving you the priesthood as your special privilege of service. Any unauthorized person who comes too near the sanctuary will be put to death."
Support for the Priests and Levites 8
The LORD gave these further instructions to Aaron: "I myself have put you in charge of all the holy offerings that are brought to me by the people of Israel. I have given all these consecrated offerings to you and your sons as your permanent share.
You are allotted the portion of the most holy offerings that is not burned on the fire. This portion of all the most holy offerings—including the grain offerings, sin offerings, and guilt offerings—will be most holy, and it belongs to you and your sons.
You must eat it as a most holy offering. All the males may eat of it, and you must treat it as most holy.
"All the sacred offerings and special offerings presented to me when the Israelites lift them up before the altar also belong to you. I have given them to you and to your sons and daughters as your permanent share. Any member of your family who is ceremonially clean may eat of these offerings.
"I also give you the harvest gifts brought by the people as offerings to the LORD—the best of the olive oil, new wine, and grain.
All the first crops of their land that the people present to the LORD belong to you. Any member of your family who is ceremonially clean may eat this food.
"Everything in Israel that is specially set apart for the LORD 
also belongs to you.
"The firstborn of every mother, whether human or animal, that is offered to the LORD will be yours. But you must always redeem your firstborn sons and the firstborn of ceremonially unclean animals.
Redeem them when they are one month old. The redemption price is five pieces of silver 
(as measured by the weight of the sanctuary shekel, which equals twenty gerahs).
"However, you may not redeem the firstborn of cattle, sheep, or goats. They are holy and have been set apart for the LORD. Sprinkle their blood on the altar, and burn their fat as a special gift, a pleasing aroma to the LORD.
The meat of these animals will be yours, just like the breast and right thigh that are presented by lifting them up as a special offering before the altar.
Yes, I am giving you all these holy offerings that the people of Israel bring to the LORD. They are for you and your sons and daughters, to be eaten as your permanent share. This is an eternal and unbreakable covenant 
between the LORD and you, and it also applies to your descendants."
And the LORD said to Aaron, "You priests will receive no allotment of land or share of property among the people of Israel. I am your share and your allotment.
As for the tribe of Levi, your relatives, I will compensate them for their service in the Tabernacle. Instead of an allotment of land, I will give them the tithes from the entire land of Israel.
"From now on, no Israelites except priests or Levites may approach the Tabernacle. If they come too near, they will be judged guilty and will die.
Only the Levites may serve at the Tabernacle, and they will be held responsible for any offenses against it. This is a permanent law for you, to be observed from generation to generation. The Levites will receive no allotment of land among the Israelites,
because I have given them the Israelites' tithes, which have been presented as sacred offerings to the LORD. This will be the Levites' share. That is why I said they would receive no allotment of land among the Israelites."
The LORD also told Moses,
"Give these instructions to the Levites: When you receive from the people of Israel the tithes I have assigned as your allotment, give a tenth of the tithes you receive—a tithe of the tithe—to the LORD as a sacred offering.
The LORD will consider this offering to be your harvest offering, as though it were the first grain from your own threshing floor or wine from your own winepress.
You must present one-tenth of the tithe received from the Israelites as a sacred offering to the LORD. This is the LORD's sacred portion, and you must present it to Aaron the priest.
Be sure to give to the LORD the best portions of the gifts given to you.
"Also, give these instructions to the Levites: When you present the best part as your offering, it will be considered as though it came from your own threshing floor or winepress.
You Levites and your families may eat this food anywhere you wish, for it is your compensation for serving in the Tabernacle.
You will not be considered guilty for accepting the LORD's tithes if you give the best portion to the priests. But be careful not to treat the holy gifts of the people of Israel as though they were common. If you do, you will die."