Numbers 18:4
They will be joined to you, and they will keep the responsibility of the tent of assembly for the entire service of the tent; a stranger may not come near you.
Numbers 1:51
And when the tabernacle is set out, the Levites will {take it down}, and when encamping the tabernacle the Levites will set it up; the stranger that approaches [it] will be put to death.
Numbers 3:10
But you will count Aaron and his descendants; they will keep their priesthood, and the stranger who approaches will be put to death."
1 Samuel 6:19
He struck seventy men among the men of Beth Shemesh because they looked into the ark of Yahweh. So the people mourned because Yahweh had struck a great blow among the people.
2 Samuel 6:6-7
When they came to the threshing floor of Nakon, Uzza reached out to the ark of God and took hold of [it], because the oxen had stumbled.