(1) بَابُ مَا جَاءَ فِي كَفَّارَةِ الْمَرَضِ
Narrated `Aisha:
(the wife of the Prophet) Allah's Messenger (ﷺ) said, "No calamity befalls a Muslim but that Allah expiates some of his sins because of it, even though it were the prick he receives from a thorn."
Reference: Sahih al-Bukhari 5640
In-book reference: Book 75, Hadith 1
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 7, Book 70, Hadith 544