In the Name of Allah, the All-Beneficent, the All-Merciful.
May Allah bless Muhammad and his Family and damn their enemies.
Sheikh Yasser al-Habib enlightens us here on the reality of Abu Bakr being in Medina in the first place in order to even allegedly lead the final prayer. He discusses how Abu Bakr defied the final order of the Prophet (peace be upon him and his family) to join the army of Usamah.