Numbers 4:15

And when Aaron and his sons had made an end of covering the
sanctuary
Not the holy place, nor the most holy place, for these were not covered by them; but "the holy things" in them, as the Septuagint version, the ark, shewbread table and all "the vessels of the sanctuary"; all appertaining to those holy things, which are before mentioned. Jarchi interprets the "sanctuary", or the "holiness", of the ark and altar,

and all the vessels of the sanctuary;
of the candlestick and the instruments of ministry:

as the camp is to set forward;
which made the covering of them necessary, in order to their being carried as that moved:

after that the sons of Kohath shall come to bear [it];
or rather them, all the holy things, and their vessels, and that upon their shoulders:

but they shall not touch [any] holy thing;
even in bearing them, neither the ark nor any other, only the staves and bar, on which they were carried: lest they die; by the immediate hand of God:

these [things are] the burden of the sons of Kohath, in the tabernacle
of the congregation;
the above things, the ark which they were to bear on their shoulders, and not make use of wagons to carry them.