"What Hadhrath Umar seems to have forgotten when recollecting the event   is the fact that not all those present in the Saqifa gave Bayya to   Hadhrath Abu Bakr, and they were adamant that their loyalties lay with   another man:
              
“Umar stood up saying, “Who among you would be agreeable to leave Abu   Bakr whom the Prophet gave precedence?” and he gave him the oath of   allegiance. The people followed [Umar]. The Ansar said, or some of them   said “We will not give the oath of allegiance [to anyone] except Ali”.
              History of Tabari, English translation, Volume 9 p 186"
             
          
          However, this is a weak narration because it is narrated by Ibn   Humayd who is not reliable; Tabari, a historian, has been criticized by   the scholars of Hadith for his reliance on weak narrators such as Ibn   Humayd.  He has even been accused of being “mutashhi`” or Shia-leaning,   due to his over-reliance on Shia narrations.  And it is for this reason   that the Shia are quick to quote from Tabari, attempting to pass it off   each and every narration as authentic to the Sunnis, when in fact many   narrations are from Shia and considered unreliable.  In his defense,   however, Tabari simply collected Hadith and did not claim to   authenticate them, but rather left that upto the scholars of Hadith to   do.  Therefore, Tareekh al-Tabari contains both strong and weak   narrations;  this particular narration is weak.  Ibn Humayd has been   labelled by the Muhadditheen as an outright liar and shameless forger.    Imam Dhahabi and Shaikh al-Islam have declared him to be weak.  We read:
          “I have never seen a natural liar, except for two persons: Sulayman ash-Shadhakuni and Muhammad ibn Humayd.”
            (Tahdhib al-Kamal, Vol.25, p.105)
          
          Answering-Ansar has used these two narrations in order to further   their argument in Chapter 5 of their article.  Therefore, to read our   rebuttal, please refer to our Response to Chapter 5.
          We have dealt with this topic more in our rebuttal to Chapter 5.
          Written By: Ibn al-Hashimi, www.ahlelbayt.com