The Messenger of Allah ﷺ said, "Fever and headache continue to afflict the servant, both man and woman, even when their sins weigh as much as Mount Uhud, and they do not leave them until not even a mustard seed's weight of sin remains."
قال رسول الله ﷺ: لا تزال المليله والصداع بالعبد والأمة، وإن عليهما من الخطايا مثل أحد، فما يدعهما وعليهما مثقال خردلة.
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Abu Yaala narrated it (6124, Athari edition) from Suwayd bin Saeed, who said, Damam narrated to us, from Musa bin Wardan, from Abu Hurairah, and he mentioned something similar.Haythami said in Majma (3012), "Abu Yaala narrated it, and its narrators are trustworthy."I say, this is as he said, except that Suwayd bin Saeed, although Muslim narrated from him, is disputed. Abdullah bin Ahmad said, "I presented to my father the hadiths of Suwayd from Damam bin Ismail, and he said to me, 'Write them all down, for he is sound,' or he said, 'trustworthy.'" Maimuni said, on the authority of Ahmad, "I know nothing but good of him." Ibn Main and Nasai and others criticized him, but the conclusion regarding him is that his hadith is hasan, especially with respect to Damam bin Ismail.Likewise, Musa bin Wardan, Abu Umar the Egyptian, is disputed, but his hadith is hasan when he does not contradict others.And "malilah" is the heat of fever that occurs in the bones.