Numbers 4:17

14 and they shall put upon it all the vessels thereof, wherewith they minister about it, the firepans, the flesh-hooks, and the shovels, and the basins, all the vessels of the altar; and they shall spread upon it a covering of sealskin, and put in the staves thereof.

15 And when Aaron and his sons have made an end of covering the sanctuary, and all the furniture of the sanctuary, as the camp is set forward; after that, the sons of Kohath shall come to bear it: but they shall not touch the sanctuary, lest they die. These things are the burden of the sons of Kohath in the tent of meeting.

16 And the charge of Eleazar the son of Aaron the priest shall be the oil for the light, and the sweet incense, and the continual meal-offering, and the anointing oil, the charge of all the tabernacle, and of all that therein is, the sanctuary, and the furniture thereof.

17 And Jehovah spake unto Moses and unto Aaron, saying,

18 Cut ye not off the tribe of the families of the Kohathites from among the Levites;

19 but thus do unto them, that they may live, and not die, when they approach unto the most holy things: Aaron and his sons shall go in, and appoint them every one to his service and to his burden;

20 but they shall not go in to see the sanctuary even for a moment, lest they die.