Jami` at-Tirmidhi 966
جامع الترمذي#966SahihAbu Sa'eed Al-Khudri (may Allah be pleased with him) narrated that:The Messenger of Allah said: "Nothing afflicts the believer, whether fatigue, grief, disease - even a worry that concerns him - except that by it, Allah removes something from his bad deeds
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirHasan Sahih
Al-AlbaniHasan Sahih
Bashar Awad MaaroufHasan
Zubair Ali ZaiSahih
In-book reference: 10:2