Opportunity soon offered. Unusual preparation and busy movement on the Roman side led to a council of the Moslem chiefs, and Khâlid laid his views before them. The Caliph, it was true, had given to each a separate and distinct command to meet the separate Roman armies. But the field had changed, and Abu Bekr would surely now approve the assumption of absolute command by a single general. The merit in the Caliph’s eyes would be the same for all; the merit in the sight of the Lord, the same. ‘Come now,’ he added, to disarm their jealousy, ‘and we shall vary the supreme command, each taking it in succession for the day, and, if ye will, let the first be mine.’ The success of Khâlid in Irâc added weight to his words. The proposal thus adroitly made was unanimously agreed to. The Chiefs expected that, when the occasion passed, the old system would be reverted to. But the change, once made, stood good; and the supreme command in Syria was thenceforward vested in a single hand.[167] [Sidenote: A Roman general gained over by Khâlid.] Meanwhile Khâlid had sown dissension in the enemy’s camp, and gained over at least one of their leading officers. The facts are obscure, and the episode, as told by tradition, strange. But so much appears, that a general, Jâreja by name, perhaps of Arab blood and imbued with Bedouin sympathies, was persuaded by Khâlid to embrace his cause, and to promise that, at the decisive moment, he would leave the Roman and join the Moslem side.[168] [Sidenote: Moslem army arranged in battalions.] The powers conferred on Khâlid were soon put to the test, and that to good purpose. His first care was to organise the army as a whole. ‘The Romans,’ he said, ‘are a vast and imposing multitude, and we but few to look at. Now no disposition swelleth numbers to the eye like that of separate battalions.’ So he divided the troops into forty battalions, each about a thousand strong and under a trusted leader.[169] These he arranged so that one half formed the centre, under Abu Obeida. Ten battalions were then assigned to each wing, of which one was led by Amru and Shorahbîl; the other by Yezîd, whose aged father, Abu Sofiân, was bid to go from troop to troop, and rouse their ardour by martial declamation.[170] [Sidenote: The Roman army advances;]