Leviticus 22:10

10 a“A lay person shall not eat of a holy thing; no foreign guest of the priest or hired worker shall eat of a holy thing,

Numbers 3:38

38Those who were to camp before the tabernacle on the east, before the tent of meeting toward the sunrise, were Moses and Aaron and his sons, bguarding the sanctuary itself, to protect
Hebrew guard
the people of Israel. And any outsider who came near was to be put to death.

Numbers 16:40

40to be a reminder to the people of Israel, so dthat no outsider, who is not of the descendants of Aaron, should draw near to burn incense before the Lord, lest he become like Korah and his company—as the Lord said to him through Moses.

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