2 Kings 3:21

21 When all the Moabites heard that the kings had come up to fight against them, all who were able to put on armor, from the youngest to the oldest, were called out and were drawn up at the frontier.

2 Kings 3:21 In-Context

19 You shall conquer every fortified city and every choice city; every good tree you shall fell, all springs of water you shall stop up, and every good piece of land you shall ruin with stones."
20 The next day, about the time of the morning offering, suddenly water began to flow from the direction of Edom, until the country was filled with water.
21 When all the Moabites heard that the kings had come up to fight against them, all who were able to put on armor, from the youngest to the oldest, were called out and were drawn up at the frontier.
22 When they rose early in the morning, and the sun shone upon the water, the Moabites saw the water opposite them as red as blood.
23 They said, "This is blood; the kings must have fought together, and killed one another. Now then, Moab, to the spoil!"
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.