But Jeroboam caused an ambushment to come about behind them,
 &c.] While Abijah was making his oration, he detached a party from his army, which got about, and lay in ambush, behind the army of Abijah: 
 so they were before Judah;
 Jeroboam and the greater part of his army: 
 and the ambushment was behind them;
 which Jeroboam had sent thither.