Joel 3:2

The valley of Jehoshaphat. — Some fifty years before Joel prophesied the kingdom of Judah had been menaced by an imposing confederacy of hostile tribes. It was an occasion of great anxiety. A national fast was proclaimed, and after it Jehoshaphat engaged and completely routed the enemy in a valley in the wilderness of Tekoa. (See 2 Chronicles 20) The victory was an occasion of immense exultation, and seems to supply the imagery with which Joel describes the day of the Lord. The name of Jehoshaphat was at some period given to the Kedron Valley, but it is here used rather in its grammatical meaning as the scene of the Divine judgment, the words signifying “the valley where Jehovah judgeth.”