God commanded Moses to number the fighting men in the first chapter of Numbers. You might notice that God is looking for people He can “count on”.  The phrase “able to go to war” is used fourteen times in the first chapter alone.
Numbers 1:44-46, tells us the final total of the census.  It says, “These are those who were listed, whom Moses and Aaron listed with the help of the chiefs of Israel, twelve men, each representing his fathers’ house. So all those listed of the people of Israel, by their fathers’ houses, from twenty years old and upward, every man able to go to war in Israel— all those listed were 603,550.”

That’s a lot of people that could be counted on.  It has been reasonably estimated that a population capable of producing that many men of fighting age would probably be around 2.5 million people or more.  At the beginning of Exodus, we see about 70 of Abraham’s descendants going down to Egypt to escape the famine in the land. Many commentators have observed that this number represents, at least to some degree, a fulfillment of God’s promise to Abraham to make the “number” of his descendants as numerous as the stars in the sky.  There were literally millions.

As we will read later in Chapter 14, however, when the chips are down, God finds that out of all these men there were only two who could really be counted on; Joshua and Caleb. There’s a difference between being “counted in” and being “counted on.”
Wiersbe asks an interesting question in his commentary on this section. “If God were to number the believers in the church today according to their ability to wage spiritual warfare, we wonder how big the army would be.” I think God is really more interested in how many who, when the chips are down, can be counted on.