Umar thought, had been averted by God would erupt later in the form of the First Fitna, suggests Madelung. Consolidation Umar in his sermon asserted that "the necks of all Muslims were stretched [in obedience] for Abu Bakr," though Madelung considers it more likely that his authority was highly precarious at first. After the Saqifa meeting, Abu Bakr reportedly headed to the Prophet's Mosque and gave his inaugural speech there. Abbas and Hazleton comment that Muhammad was already buried by this time, with the exclusion of Abu Bakr from the funeral rites. With the help of the Banu Aslam and Banu Aws tribes, Umar is then said to have dominated the streets to secure the pledges of allegiance from the Medinans, according to Madelung. In chronological order, Abu Bakr obtained the backing of Uthman and of the Banu Umayyad, of Sa'd and Abd al-Rahman ibn Awf, of the Banu Zuhra, of Zubayr, and finally of Ali. Ali's opposition Al-Baladhuri reports that the Banu Hashim and some companions gathered at Ali's house after learning about the appointment of Abu Bakr. Among them were Muhammad's uncle Abbas and Zubayr. These protesters held that Ali was the rightful successor to Muhammad, possibly referring to Muhammad's announcement at Ghadir Khumm. Miqdad, Salman, Abu Dharr, Talha were also among the companions who supported Ali's cause. Threats against Ali Abu Bakr is said to have tasked Umar with securing Ali's pledge of allegiance. As noted by al-Tabari, the latter then led an armed mob to Ali's residence and threatened to set the house on fire if Ali and his supporters would not pledge their allegiance to Abu Bakr. The scene soon grew violent, but the mob retreated without Ali's pledge after his wife Fatima pleaded with them, as reported in the Sunni al-Imama wa al-siyasa. Alternatively, al-Baladhuri states that Ali capitulated and pledged allegiance to Abu Bakr immediately after Umar's threat. In contrast, the canonical Sahih al-Bukhari and Sahih Muslim relate that Ali pledged to Abu Bakr after Fatima died sometime later. Boycott of Ali Madelung believes that Abu Bakr later placed a boycott on Ali and also on the Banu Hashim to abandon their support for Ali. As a result, prominent men ceased to speak to Ali, as related in a Sunni hadith attributed to Aisha. Those who initially supported Ali gradually turned away and pledged their allegiance to Abu Bakr, adds Jafri. At the