What is the authenticity of the Ansar's desire to pledge allegiance to Sa'd ibn Ubadah for the Caliphate, and why did Ali believe he was more deserving of it than Abu Bakr, and did Sa'd refrain from pledging allegiance to Abu Bakr and Umar until his death, and how did he die and what is the refutation against those who say his death was pre-meditated?

The Ansar wanted to pledge allegiance to Sa'd ibn Ubadah, believing they had a right to leadership and that Sa'd was one of their chiefs. However, they retracted this after the Companions clarified that leadership belonged to Quraysh.

Sa'd desired the caliphate based on this interpretation, and due to the human inclination towards leadership.

What was said, that Ali believed Sa'd was more deserving of the caliphate, is a lie and fabrication. No Companion claimed his own greater right to the caliphate over Abu Bakr.

It is well-known that Sa'd ibn Ubadah did not pledge allegiance to Abu Bakr or Umar until he died, and his abstention from the pledge did not invalidate it.

Sa'd died in his washing place. The claim that his killing was premeditated is a lie and slander. It is well-known that he was found dead in his washing place after a voice was heard saying: "We killed the master of Khazraj... Sa'd ibn Ubadah... We shot him with an arrow... and it did not miss his heart."