Sahih Bukhari

(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."

The Prophet (ﷺ) said, "No fatigue, nor disease, nor sorrow, nor sadness, nor hurt, nor distress befalls a Muslim, even if it were the prick he receives from a thorn, but that Allah expiates some of his sins for that."

The Prophet (ﷺ) said, "The example of a believer is that of a fresh tender plant, which the wind bends lt sometimes and some other time it makes it straight. And the example of a hypocrite is that of a pine tree which keeps straight till once it is uprooted suddenly.

Allah's Messenger (ﷺ) said, "The example of a believer is that of a fresh tender plant; from whatever direction the wind comes, it bends it, but when the wind becomes quiet, it becomes straight again. Similarly, a believer is afflicted with calamities (but he remains patient till Allah removes his difficulties.) And an impious wicked person is like a pine tree which keeps hard and straight till Allah cuts (breaks) it down when He wishes." (See Hadith No. 558, Vol. 9.)

Allah's Messenger (ﷺ) said, "If Allah wants to do good to somebody, He afflicts him with trials."

I never saw anybody suffering so much from sickness as Allah's Messenger (ﷺ).

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."