Sahih al-Bukhari 4699
صحيح البخاري#4699SahihNarrated Al-Bara bin Azib:Allah's Messenger (ﷺ) said, "When a Muslim is questioned in his grave, he will testify that none has the right to be worshipped but Allah and that Muhammad is Allah's Messenger (ﷺ), and that is what is meant by Allah's Statement:-- "Allah will keep firm those who believe with a Word that stands firm in this world and in the Hereafter
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: 65:221