The waters - The streams which run from the mountain district of Ephraim into the Jordan in the district of Beth-shan, forming great pools and marshes, which the Midianites fleeing south would have to cross before they could reach the Jordan fords.
All the men of Ephraim - They had taken no previous part in the rising against Midian: nor had Gideon, of the smaller tribe of Manasseh, presumed before to summon his more powerful and arrogant brethren of the great tribe of Ephraim (see Joshua 17:14-18).