 Complete the following phrase:  He led a delegation of seventy Kindite warriors to the Islamic prophet Muhammad and converted to Islam. Following Muhammads death in 632, he and his tribe withheld the customary payment to the nascent Muslim state and apostasized during the Ridda wars. After their subsequent defeat at the Zurqan pasture in Hadhramawt, they and their families took up position at the al-Nujayr fort in Yemen and were besieged by the Muslim forces. Al-Ashath secured safe passage for a number of his relatives, but the rest of the besieged fighters were executed. He was spared but taken captive and sent to Caliph Abu Bakr r. 632634, who agreed to release him after he repented. He thereafter took up residence in Medina, capital of the caliphate, where he was married to Abu Bakrs sister, Umm Farwa. Despite an initial prohibition on former apostates participating in the Muslim conquests, during the reign of Caliph Umar r. 634644, al-Ashath joined the Muslim army of Sad ibn Abi Waqqas, which was dispatched to conquer Iraq from the Sasanian Empire. During that campaign, he fought in the battles of Qadisiyya, Ctesiphon, 