"Elisha went to Damascus while King Ben-hadad was ill." His illness had derived from his unhappiness. For he had been deeply afflicted by the fact that, in the war of Samaria, his armies had been defeated and that, at the same time, his people had been chased from the city when he had hoped that his victory would occur immediately. His entire army had fled and sunk into shame and dishonor, and he was troubled in his mind because of this. In addition, the anguish of his thoughts was due to something that was not responsible for his fall: he had been deceived in believing that a countless and powerful army would march against him, whereas it was later shown that there was no army at all to oppress him.
Source: ON THE SECOND BOOK OF KINGS 8:7