NET

21 Now all Moab had heard that the kings were attacking, so everyone old enough to fight was mustered and placed at the border.

Darby

21 And all the Moabites heard that the kings were come up to fight against them, and they were called together, all that were able to put on armour, and upward, and stood by the border.

KJV

21 And when all the Moabites heard that the kings were come up to fight against them, they gathered^K1999all that were able to put on armour^K2000, and upward, and stood in the border.

KJV Bible Notes

gathered: Heb. were cried together. put on armour: Heb. gird himself with a girdle.