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, aguarding 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 cthat 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.

Numbers 18:4

4They shall join you and keep guard over the tent of meeting for all the service of the tent, dand no outsider shall come near you.
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