Numbers 4:15; Numbers 4:20

15 "When Aaron and his sons have finished covering the holy objects and all the furnishings of the sanctuary, when the camp is to set out, after that the sons of Kohath shall come to carry them, so that they will not touch the holy objects and die. These are the things in the tent of meeting which the sons of Kohath are to carry.

20 but they shall not go in to see the holy objects even for a moment, or they will die."