Regarding the strength of the confronting armies,
H. A. R. Gibb in the
Encyclopaedia of Islam argues that, at best, both forces were made up of 10,000 men, and that the numbers offered in the Muslim sources are "highly exaggerated", especially as regards the Byzantines. David Morray in the
Oxford Companion to Military History, however, places both armies at approximately 20,000 strong. The Byzantines were led by Heraclius' brother
Theodore, as well as by a figure called "Wardan" according to al-Azdi, possibly a corruption of the Armenian name Vardan. The Muslim sources name him as the
patrikios (commander) of Emesa, which was the major Byzantine base of operations in Syria in the early period of the Muslim conquests. According to Kaegi, he possibly commanded fresh reinforcements from the north, including Armenians, or from the army that had accompanied Heraclius to Syria. In
Al-Tabari's account, the Byzantines are led by the governor of
Jerusalem,
Aretion. The Arab army consisted of three separate contingents, with either Khalid or, less likely, Amr, as the overall commander. Some chronicles also state that Sergius, the governor of
Caesarea was present at the battle, but others say he died in February. Despite the evidence from primary sources on both sides that the Byzantine army numbered 40,000 men, it should be assumed that this number is overestimated, since for such a large army, the losses of 1,700 killed and 5,000 wounded are not so great as to make it unable to withstand half the size of the Arab army. Therefore, we can assume that the Byzantine army was approximately equal to the Arab army in terms of numbers. Moreover, it is fair to say that the city police was sent against the Arabs, whose training was not the best. ==Battle ==