question #3 Sahih al-Bukhari 5647, Book 75, Hadith 7 : What is the relationship between physical ailments and spiritual rewards in Islam?

I visited the Prophet (ﷺ) during his ailments and he was suffering from a high fever. I said, “You have a
high fever. Is it because you will have a double reward for it?” He said, “Yes, for no Muslim is
afflicted with any harm but that Allah will remove his sins as the leaves of a tree fall down.”