Sahih al-Bukhari 5660
صحيح البخاري#5660SahihNarrated `Abdullah bin Mas`ud:I visited Allah's Messenger (ﷺ) while he was suffering from a high fever. I touched him with my hand and said, "O Allah's Messenger (ﷺ)! You have a high fever." Allah's Messenger (ﷺ) said, "Yes, I have as much fever as two men of you have." I said, "Is it because you will get a double reward?" Allah's Messenger (ﷺ) said, "Yes, no Muslim is afflicted with harm because of sickness or some other inconvenience, but that Allah will remove his sins for him as a tree sheds its leaves
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: 75:20