דברי הימים ב, פרק י״ח, פסוק כ״ט

Despite showing outward contempt for the prophet's warning of his impending downfall, the king of Israel is deeply unsettled. He attempts to outsmart his predicted fate on the battlefield by changing his clothes and hiding his identity [מצודת ציון]. The primary approach among commentators is that while the king does not fully believe the prophet, the warning still causes him great fear. He worries that the Arameans have heard the prophecy and will focus all their attacks exclusively on him. To protect himself, he informs Jehoshaphat that he will enter the battle disguised in regular clothes so the enemy will not recognize him as the king of Israel [רש״י, מצודת דוד, חומת אנך, ביאור שטיינזלץ].

At the same time, he instructs Jehoshaphat to wear his usual royal armor and special weapons. To ease any concerns, he reassures Jehoshaphat that there is no danger in being recognized. Because the prophecy of doom was directed solely at the king of Israel, the Arameans will only be hunting for him [רש״י, מצודת דוד, ביאור שטיינזלץ].

A completely different perspective suggests a more tense exchange between the two leaders. According to this view, the king of Israel actually demands that Jehoshaphat also remove his royal garments so that both of them can enter the battle in disguise. Jehoshaphat objects to this plan, arguing that someone must represent royal majesty on the battlefield. He counters with a condition, insisting that if he is to disguise himself, the king of Israel must wear his own royal clothes. When the king of Israel refuses and proceeds to disguise himself anyway, Jehoshaphat chooses to keep his royal garments on for the battle [חומת אנך].