Numbers, the fourth book of the Torah, describes the journey of the Jewish people from the foot of Mount Sinai to the threshold of the Land of Israel. The first section begins as G-d tells Moses to take a census of the adult Jewish males in the desert (Bemidbar, in Hebrew). The purpose of the census is to form the adult males into an army, should it be necessary to fight the non-Jewish occupants of the Land of Israel.
Numbers 1:1 - 4:20
G-d told Moses, “take a census of all the congregation of the Israelites by families:"
Numbers 1:2
The Torah records only the total number of men, and not the number of families, in each tribe. Nevertheless, G-d had the families counted, in order to stress the centrality of the family in Judaism.
Our individual and national goals are certainly important, but the Torah also demands of us the selflessness necessary to forge the family unit.
A husband and wife are two separate people, with their own natures,
desires, and even missions in life; yet each must work for and work with the other, completing and complementing each other and merging into one harmonious, loving unit.
The strife and breakdown of communication from which the world suffers stem from selfishness—i.e., viewing others merely as means to be exploited for personal ends. In contrast, the Torah commands us to love our neighbors as ourselves. The primary setting in which this commandment is fulfilled is that of our families. Inasmuch as loving our fellow Jew is an expression of our love of G-d, loving our fellow Jew enhances our love of G-d. Love of G-d, in turn, brings us to love His Torah and study it—not merely out of our obligation to do so, but out of love. This threefold love of our fellow Jew, of G-d, and of the Torah ripples outward from the family setting and affects the entire world for the better.
—from Daily Wisdom #1