(64) باب هَلْ يَخُصُّ شَيْئًا مِنَ الأَيَّامِ
Narrated 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?"
Reference: Sahih al-Bukhari 1987
In-book reference: Book 30, Hadith 94
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 3, Book 31, Hadith 208