Israelites still at Mt. Sinai:
The Book of Numbers comes from the two “numberings” of the first and second generations of Israelites in the wilderness.  Numbers details the two generations wanderings, geographical and spiritual, in the wilderness of the Sinai.  The first part of the book (ch. 1-25) details the first generation in the wilderness, and the second part of the book (ch. 26-36) details the second generation in the wilderness.  The book ends (ie, the 40 years) with the Israelites at the plains of Moab at the doorstep to the Promised Land.

The Census:
The Book of Numbers opens up with a census of the people for “all the men in Israel of twenty years or more who are fit for military service.” (Num. 1:3)  Israelis arrayed in a war camp arrangement.  It is in the midst of the desert wilderness surrounded by enemies that want to kill them.  They will have to defeat enemies to take control of the Promised Land. Thus, a census is done in part to determine the number of fighting men to comprise the army of Israel.  After polling all twelve tribes of Israel: “The total number of the Israelites of twenty years or more who were fit for military service, registered by ancestral houses, was six hundred and three thousand five hundred and fifty.” (Num. 1:45-46)  Or: 603,550 military age men.  This seems like a very large number, especially if including women and children, which would put the camp of Israel up into the 1-2 million. Scholars debate the veracity of this number and if it should be smaller or not.

The Levites Exempted:
Yet, the amount of attention paid to the Levites and the Levitical system, the change from the Covenant at Mt. Sinai to the Levitical system and law, due to the sin of the Golden Calf, suggests there is need for caution. The Levites camp directly around the Tabernacle acting as a buffer between the “lay tribes” and Yahweh.  The Levites mediate the interaction now between Israel and God.  After the Golden Calf incident, the firstborn sons of Israel were “laicized” and now the Levite men alone are the royal priesthood.  The Levites are exempted from the census and military service.  The Levites are in charge of the “Dwelling” with all “its equipment and all that belongs to it.” (Num. 1:50)  “They shall therefore camp around the Dwelling.” “Any layman who comes near it shall be put to death.”  Only the Levites are to approach to the Dwelling (the Meeting Tent).

The War Camp:
The Israelites are arrayed in a military style war camp, surrounding the Meeting Tent to the north, south, east and west.  Each tribe is camped “each in his own division, under the ensigns of their ancestral houses” surrounding the Meeting Tent. (Num. 2:2)  The Tabernacle is in the center.  Four groups of three tribes are at each cardinal point.  To the east are Judah, Isaachar, and Zebulum; to the south are Reuben, Simeon, and Gad; to the west are Ephraim, Manasseh, and Benjamin; and to the north are Dan, Asher, and Naphtali.  The war camp of Israel is a similar array to the Egyptian war camp as the Egyptian army surrounded the tent of Pharaoh in the middle. There is a certain amount of optimism with the Israelites as they are arrayed in a military camp prepared for conquest.