Edomites: Become Confederates of Jehoshaphat
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2 Kings 3:9, 26
So the king of Israel, the king of Judah, and the king of Edom set out, and after they had traveled a roundabout route for seven days, they had no water for their army or for their animals. / When the king of Moab saw that the battle was too fierce for him, he took with him seven hundred swordsmen to break through to the king of Edom, but they could not prevail.