Numbers 26:2

Take the sum of all the congregation of the children of Israel,.... Excepting the Levites, who were to be numbered by themselves, and at a different age; this sum was to be taken, that it might appear that all of the old generation that came out of Egypt, of the age at which this sum was taken, were now dead, excepting two, as the Lord had threatened; and partly that as they were now about to enter the land of Canaan, it might be divided to them according to their number; as well as to show the faithfulness of God to his word and promise, that he would multiply and make them fruitful, notwithstanding all their provoking sins and transgressions:

from twenty years old and upwards, throughout their father's house; all of that age in every tribe, house, and family:

all that are able to go to war in Israel; for which they must prepare, being about to enter the land of Canaan, and dispossess and drive out the inhabitants of it.