Sahih al-Bukhari 1987
صحيح البخاري#1987SahihNarrated Alqama:I asked `Aisha "Did Allah's Apostle, use to choose some special days (for fasting)?" She replied, "No, but he used to be regular (constant) (in his service of worshipping). Who amongst you can endure what Allah's Messenger (ﷺ) used to endure?
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: 30:94