Sickness is expiation for sins Sahih al-Bukhari 5644
Arabic hadith text
حَدَّثَنَا إِبْرَاهِيمُ بْنُ الْمُنْذِرِ، قَالَ حَدَّثَنِي مُحَمَّدُ بْنُ فُلَيْحٍ، قَالَ حَدَّثَنِي أَبِي، عَنْ هِلاَلِ بْنِ عَلِيٍّ، مِنْ بَنِي عَامِرِ بْنِ لُؤَىٍّ عَنْ عَطَاءِ بْنِ يَسَارٍ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم" مَثَلُ الْمُؤْمِنِ كَمَثَلِ الْخَامَةِ مِنَ الزَّرْعِ مِنْ حَيْثُ أَتَتْهَا الرِّيحُ كَفَأَتْهَا، فَإِذَا اعْتَدَلَتْ تَكَفَّأُ بِالْبَلاَءِ، وَالْفَاجِرُ كَالأَرْزَةِ صَمَّاءَ مُعْتَدِلَةً حَتَّى يَقْصِمَهَا اللَّهُ إِذَا شَاءَ "
Translation
Narrated Abu Huraira
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.)