وَمَا أَصَابَكُم مِّن مُّصِيبَةٍ فَبِمَا كَسَبَتْ أَيْدِيكُمْ
And whatever of misfortune befalls you, it is because of what your hands have earned.
means, `whatever disasters happen to you, O mankind, are because of sins that you have committed in the past.'
وَيَعْفُو عَن كَثِيرٍ
And He pardons much.
means, of sins;
`He does not punish you for them, rather He forgives you.'
وَلَوْ يُوَاخِذُ اللَّهُ النَّاسَ بِمَا كَسَبُواْ مَا تَرَكَ عَلَى ظَهْرِهَا مِن دَابَّةٍ
And if Allah were to punish men for that which they earned, He would not leave a moving creature on the surface of the earth. (35;45)
According to a Sahih Hadith;
وَالَّذِي نَفْسِي بِيَدِهِ مَا يُصِيبُ الْمُوْمِنَ مِنْ نَصَبٍ وَلَاا وَصَبٍ وَلَاا هَمَ وَلَاا حَزَنٍ إِلاَّ كَفَّرَ اللهُ عَنْهُ بِهَا مِنْ خَطَايَاهُ حَتْى الشَّوْكَةِ يُشَاكُهَا
By the One in Whose Hand is my soul, no believer is stricken with fatigue, exhaustion, worry or grief, but Allah will forgive him for some of his sins thereby -- even a thorn which pricks him.
Imam Ahmad recorded that Mu`awiyah bin Abi Sufyan, may Allah be pleased with him, said,
"I heard the Messenger of Allah say;
مَا مِنْ شَيْءٍ يُصِيبُ الْمُوْمِنَ فِي جَسَدِهِ يُوْذِيهِ إِلاَّ كَفَّرَ اللهُ تَعَالَى عَنْهُ بِهِ مِنْ سَيِّيَاتِه
No physical harm befalls a believer, but Allah will expiate for some of his sins because of it."
Imam Ahmad also recorded that `A'ishah, may Allah be pleased with her, said,
"The Messenger of Allah said;
إِذَا كَثُرَتْ ذُنُوبُ الْعَبْدِ وَلَمْ يَكُنْ لَهُ مَا يُكَفِّرُهَا ابْتَلَهُ اللهُ تَعَالَى بِالْحَزَنِ لِيُكَفِّرَهَا
If a person commits many sins and has nothing that will expiate for them, Allah will test him with some grief that will expiate for them."
وَمَا أَنتُم بِمُعْجِزِينَ فِي الاَْرْضِ
وَمَا لَكُم مِّن دُونِ اللَّهِ مِن وَلِيٍّ وَلَا نَصِيرٍ