Numbers 18:7-9

Amplified Bible

⁷ Therefore you and your sons with you shall attend to your priesthood for everything concerning the altar [of burnt offering and the altar of incense] and [of the Holy of Holies] within the veil, and you are to serve. I am giving you the priesthood as a bestowed service, but the stranger (outsider, layman) who approaches shall be put to death.”^(A)

The Priests’ Portion

⁸ Then the Lord spoke to Aaron, “Now behold, I [the Lord] have entrusted you with My heave offerings, even all the holy gifts of the Israelites, I have given them to you as a portion, and to your sons as a continual allotment.^{(B) 9} This shall be yours of the most holy things, [reserved] from the fire: every offering of the people, every grain offering and sin offering and guilt offering, which they shall render (give) to Me, shall be most holy for you and for your sons.