Sahih al-Bukhari Book 10, Hadith 73
the mother of the believers: Allah's Messenger (ﷺ) in his illness said, "Tell Abu Bakr to lead the people in
prayer." I said to him, "If Abu Bakr stands in your place, the people would not hear him owing to his
(excessive) weeping. So please order `Umar to lead the prayer." `Aisha added I said to Hafsa, "Say to
him: If Abu Bakr should lead the people in the prayer in your place, the people would not be able to
hear him owing to his weeping; so please, order `Umar to lead the prayer." Hafsa did so but Allah's
Apostle said, "Keep quiet! You are verily the Companions of Joseph. Tell Abu Bakr to lead the people
in the prayer. " Hafsa said to `Aisha, "I never got anything good from you."
"The Prophet (ﷺ) became sick and when his disease became aggravated, he said, "Tell Abu Bakr to lead the prayer." `Aisha said, "He is a softhearted man and would not be able to lead the prayer in your place." The Prophet (ﷺ) said again, "Tell Abu Bakr to lead the people in prayer." She repeated the same reply but he said, "Tell Abu Bakr to lead the people in prayer. You are the companions of Joseph." So the messenger went to Abu Bakr (with that order) and he led the people in prayer in the lifetime of the Prophet.
Anas bin Malik Al-Ansari, told me, "Abu Bakr used to lead the people in prayer during the fatal illness of the Prophet (ﷺ) till it was Monday. When the people aligned (in rows) for the prayer the Prophet (ﷺ) lifted the curtain of his house and started looking at us and was standing at that time. His face was (glittering) like a page of the Qur'an and he smiled cheerfully. We were about to be put to trial for the pleasure of seeing the Prophet, Abu Bakr retreated to join the row as he thought that the Prophet (ﷺ) would lead the prayer. The Prophet (ﷺ) beckoned us to complete the prayer and he let the curtain fall. On the same day he died."