Aroer was a city in the lot of Gad and Reuben, Num_32:34. In David’s time it was in the hand of the Jews, 1Sa_30:28, but in Isaiah’s time it belonged to Syria, Isa_17:2, and here it is reckoned to the Moabites. The inhabitants of it are called to
stand by the way, and seeing the Moabites fleeing, to ask what news. Others think that Aroer was at this time a city of the Ammonites, and here called unto to see their neighbours the Moabites fleeing before their enemies.