Sahih al-Bukhari 733
صحيح البخاري#733SahihNarrated Anas bin Malik:Allah's Messenger (ﷺ) fell from a horse and got injured so he led the prayer sitting and we also prayed sitting. When he completed the prayer he said, "The Imam is to be followed; if he says Takbir then say Takbir, bow if he bows; raise your heads when he raises his head, when he says, 'Sami`a l-lahu liman hamidah say, 'Rabbana laka l-hamd', and prostrate when he prostrates
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 10:127