מלכים ב, פרק ט׳, פסוק י״ט

After the first messenger fails to return, King Jehoram sends a second horseback rider to uncover the intentions of the approaching group and find out if they come in peace. Unlike the first scout who stopped at a safe distance, the second rider goes directly up to the approaching men. Because he saw that no harm had come to his predecessor, he feels secure enough to approach the group closely [מלבי״ם].

Upon arrival, the rider asks the king's question, but Jehu refuses to answer. Instead, Jehu dismisses the inquiry and orders the messenger to turn around and stand at the back of the rebel camp. The rider obeys the command, abandoning his royal mission and joining the uprising [ביאור שטיינזלץ].

The failure of both riders to return makes it entirely clear to King Jehoram that his messengers have defected to the approaching force. This realization, combined with the watchman identifying Jehu by his hasty riding style, forces the king to take matters into his own hands. Recognizing the immediate threat, he orders his chariot to be prepared and rides out to the battlefield himself [אברבנאל].