Musnad Ahmad 1153:1858

Abu Mu’awiyah narrated to us, he said: Al-A’mash narrated to us, from Ibrahim, from Al-Aswad, from ‘Aishah, who said: When the Messenger of Allah (ﷺ) became heavy [with illness], Bilal came to inform him of the prayer. He said: "Command Abu Bakr to lead the people in prayer." I said: "O Messenger of Allah, Abu Bakr is a soft-hearted man, and whenever he stands in your place, he will not be heard by the people. If only you would command ‘Umar?" He said: "Command Abu Bakr to lead the people in prayer." I said to Hafsah: "Tell him." So Hafsah said to him: "O Messenger of Allah, Abu Bakr is a soft-hearted man, and whenever he stands in your place, he will not be heard by the people. If only you would command ‘Umar?" He said: "You are indeed the companions of Yusuf. Command Abu Bakr to lead the people in prayer." She said: So they commanded Abu Bakr to lead the people in prayer. When he entered into the prayer, the Messenger of Allah (ﷺ) felt a lightness in himself. She said: So he stood, being supported between two men, his feet dragging on the ground, until he entered the mosque. When Abu Bakr heard his presence, he went to step back, but the Messenger of Allah (ﷺ) gestured to him: "Stay as you are." The Messenger of Allah (ﷺ) came until he sat to the left of Abu Bakr. The Messenger of Allah (ﷺ) was praying with the people while sitting, and Abu Bakr was standing, Abu Bakr following the prayer of the Messenger of Allah (ﷺ), and the people following the prayer of Abu Bakr.