Numbers 26:1-4

And it came to pass after the plague, that Jehovah spake unto Moses and unto Eleazar the son of Aaron the priest, saying, Take the sum of all the congregation of the children of Israel, from twenty years old and upward, by their fathers’ houses, all that are able to go forth to war in Israel. And Moses and Eleazar the priest spake with them in the plains of Moab by the Jordan at Jericho, saying, Take the sum of the people, from twenty years old and upward; as Jehovah commanded Moses and the children of Israel, that came forth out of the land of Egypt.