their national prejudices and newly-awakened religious zeal, he exhorted them to wrest the long-coveted Syria out of the infidels' hands. His proposal was hailed with satisfaction by all those to whom it was addressed, and in a short space of time a considerable army was assembled around Medinah, waiting for the caliph's orders. Yezid ibn Abi Sufiyan was appointed commander-in-chief of the forces, and received immediate orders to march. Nothing could have been more moderate than the instructions which Abu Bekr delivered to his general for the conduct of the war. He was to respect the lives of women, children, and aged persons ; to permit no wanton mischief or destruction of property, and to adhere religiously to any covenant or treaty which they might make with the opposite side. The Emperor Heraclius made immediate preparations for averting the threatened invasion, but his hastilycollected and ill-organised forces were defeated in the very first engagement, while the Arabs scarcely suffered any loss. Encouraged by the success of their countrymen the inhabitants of Mecca and of the Hejjâz flocked to Abu Bekr's standard, and another division, under ''Amer ibn el 'As, the future conqueror of Egypt, was despatched into Palestine. Abu Obeidah ibn el J errali, of whom we shall hear more anon, was at the same time sent to take the command in Syria ; but, meeting with some reverses, he was in turn superseded by Khalid ibn el YValid, who was recalled from Irak for that purpose. This warrior's achievements against "the Infidels" had, during Mohammed's lifetime, earned for him the title of " The drawn Sword of God," and his name had already become a terror to the Greeks. The important town of Bostra was the first to yield, being betrayed by its governor Bomanus, and the Saracens thus obtained a footing in Syria, of which they were not slow to take advantage.