sentences:  After he was freed the caliph reinvested him with the governorship of Khurasan, although Muhammad never asserted his authority there.Several anti-Saffarid partisans in Khurasan, such as Ahmad al-Khujistani and Rafi' ibn Harthama, placed Muhammad's name in the khutba in areas they managed to control, but Muhammad never exercised any actual authority over them.After being freed by the caliph Muhammad took up residence in Baghdad and from there attempted to gain the offices held by Ubaydallah ibn Abdallah.