Numbers 1:3

3 from twenty years old and upward, everyone in Israel able to go to war. You and Aaron shall enroll them, company by company.

Numbers 1:3 In-Context

1 The Lord spoke to Moses in the wilderness of Sinai, in the tent of meeting, on the first day of the second month, in the second year after they had come out of the land of Egypt, saying:
2 Take a census of the whole congregation of Israelites, in their clans, by ancestral houses, according to the number of names, every male individually;
3 from twenty years old and upward, everyone in Israel able to go to war. You and Aaron shall enroll them, company by company.
4 A man from each tribe shall be with you, each man the head of his ancestral house.
5 These are the names of the men who shall assist you: From Reuben, Elizur son of Shedeur.
New Revised Standard Version Bible, copyright 1989, Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.