2 Kings 3:21 in the World English Bible
Now when all the Moabites heard that the kings had come up to fight against them, they gathered themselves together, all who were able to put on armor, young and old, and stood on the border.
Context
20 And it came to pass in the morning, when the meat offering was offered, that, behold, there came water by the way of Edom, and the country was filled with water.
21 And when all the Moabites heard that the kings were come up to fight against them, they gathered all that were able to put on armour, and upward, and stood in the border.
22 And they rose up early in the morning, and the sun shone upon the water, and the Moabites saw the water on the other side as red as blood: