Numbers 4:4, 15

This is the work of the descendants of Kohath in the tent of meeting, concerning the most holy things.

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 by the poles, so that they will not touch the holy objects and die. These are the things in the tent of meeting that the sons of Kohath are to carry.