Bamidbar - Sh'vi'i
Keeping Elazar Busy
G-d told Moshe to take a separate census of the family of Kehos, counting those between the ages of 30 and 50. Their job would be, when the camp travels, to transport the Aron, Table, and Menorah, with all their related utensils. Before they could do so, the kohanim would have to remove the partition (Paroches) and wrap the various vessels. They would also have to remove all the ashes from the altar and cover it before it could be moved. Only after the kohanim were finished could the family of Kehos transport the furniture of the Mishkan.
As mentioned, the family of Kehos was placed under the direction of Aharon's son Elazar. Elazar was responsible not only for the furniture, but also for the oil used to light the Menorah, the incense, the flour offerings and the anointing oil.
G-d gave Moshe and Aharon some "good advice" to protect the lives of the family of Kehos: they were not to come for the Mishkan furniture until the kohanim were finished wrapping it. To do otherwise is to court destruction.