Musnad Ahmad 4205

Translation

✧ I entered upon the Messenger of Allah ﷺ while he was suffering from a fever. I said, 'O Messenger of Allah, you are suffering from a severe fever!' The Messenger of Allah ﷺ said, 'Yes, I suffer the fever of two men among you.' I said, 'Is that because you will have a double reward?' He said, 'Yes' (or 'Indeed'). Then he said, 'No Muslim is afflicted by harm, even a thorn or something greater, except that Allah, Mighty and Majestic, removes some of his sins thereby, just as a tree sheds its leaves.'

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