In 793 Musa was appointed as governor of Damascus. Upon his arrival in Syria he undertook a monthlong expedition in the Hauran in an unsuccessful effort to hunt down the Qaysi Abu al-Haydham, who had raised the standard of rebellion a few months prior. After subsequent further attempts to kill or capture Abu Haydham likewise ended in failure, Musa was recalled by the caliph and he departed from the region, leaving Abd al-Salam ibn Humayd to manage affairs in his stead.[15]