On the first day of the second month in the second year after the people of Israel left Egypt, the Lord spoke to Moses there in the Tent of his presence in the Sinai Desert. He said, 1
References for Numbers 1:1
1.1-46 Nu 26.1-51.
"You and Aaron are to take a census of the people of Israel by clans and families. List the names of all the men
twenty years old or older who are fit for military service.
Ask one clan chief from each tribe to help you."
These are the men, leaders within their tribes, who were chosen from the community for this work:
With the help of these twelve men Moses and Aaron
called together the whole community on the first day of the second month and registered all the people by clans and families. The names of all the men twenty years old or older were recorded and counted,
as the Lord had commanded. In the Sinai Desert, Moses registered the people.
The men twenty years old or older who were fit for military service were registered by name according to clan and family, beginning with the tribe of Reuben, Jacob's oldest son. The totals were as follows:
The Levites were not registered with the other tribes,
because the Lord had said to Moses,
"When you take a census of the men fit for military service, do not include the tribe of Levi.
Instead, put the Levites in charge of the Tent of my presence and all its equipment. They shall carry it and its equipment, serve in it, and set up their camp around it.
Whenever you move your camp, the Levites shall take the Tent down and set it up again at each new campsite. Anyone else who comes near the Tent shall be put to death.
The rest of the Israelites shall set up camp, company by company, each man with his own group and under his own banner.
But the Levites shall camp around the Tent to guard it, so that no one may come near and cause my anger to strike the community of Israel."
So the people of Israel did everything that the Lord had commanded Moses.