When he finished, he said: "The Imam is appointed only to be followed. So when he bows, bow; when he raises, raise; and if he prays sitting, pray sitting."(1)

606 — Qutaybah ibn Sa'id and Yazid ibn Khalid ibn Mawhab narrated to us — the meaning [being the same] — that al-Layth narrated to them, from Abu al-Zubayr, from Jabir, who said: The Prophet, peace and blessings be upon him, fell ill, so we prayed behind him while he was sitting, and Abu Bakr was saying the takbir loudly so that the people could hear his takbir. Then he related the rest of the hadith.(2)

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(1) Its chain of transmission is authentic. Al-Qa'nabi: he is 'Abdullah ibn Maslamah.
It is in the Muwatta' of Malik, 1/135, and from his transmission al-Bukhari also recorded it (686), (1113), and (1236).
Al-Bukhari also recorded it (5658), Muslim (412), al-Nasa'i in al-Kubra (7472), and Ibn Majah (1237) via multiple chains from Hisham ibn 'Urwah, with this chain of transmission.
It is in the Musnad of Ahmad (24250) and (25149), and Sahih Ibn Hibban (2104).

(2) Its chain of transmission is authentic. Al-Layth: he is Ibn Sa'd, and Abu al-Zubayr: he is Muhammad ibn Muslim ibn Tadrus al-Makki.
Muslim recorded it (413), al-Nasa'i in al-Kubra (540), (875), and (1124), and Ibn Majah (1240) via two chains from Abu al-Zubayr, with it.
It is in the Musnad of Ahmad (14590), and Sahih Ibn Hibban (2122).
And see what preceded under number (602).

Al-Hafiz Ibn Hajar said in Fath al-Bari, 2/177: This was not during the illness of his death, peace and blessings be upon him; rather, that was when he fell from the horse, as in the narration of Abu Sufyan from Jabir [which is what preceded under number (602)]. However, Ibn Hibban clung to his statement: "And Abu Bakr was making the people hear the takbir," and said: That was only during the illness of his death, because his prayer during his first illness was in the chamber of 'A'ishah, with a group of his companions, who did not need someone to make them hear his takbir, unlike his prayer during the illness of his death, for it was in the mosque with a large gathering of the companions, so Abu Bakr needed to make them hear the takbir. End [of his words]. But there is no comfort for him in what he clung to, for making the takbir heard in this [narration] did not =