Some jobs are inherently dangerous. This was certainly the case for the Kohathites, one of the extended families among the Levites.
The early chapters of the Book of Numbers describe the tasks specified for the Kohathites, and for the other Levitical families, the Gershonites and the Merarites. Each clan must carry parts of the holy Tabernacle as the Israelites make their way through the wilderness. Only one of the clans, though -- the Kohathites -- receive a special warning: “They shall not go in to see the holy things, lest they die” (Numbers 4:20).