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Surah 35. Fatir
Ayah 7 - 8
7ٱلَّذِينَ كَفَرُوا۟ لَهُمْ عَذَابٌ شَدِيدٌ ۖ وَٱلَّذِينَ ءَامَنُوا۟ وَعَمِلُوا۟ ٱلصَّـٰلِحَـٰتِ لَهُم مَّغْفِرَةٌ وَأَجْرٌ كَبِيرٌ
8أَفَمَن زُيِّنَ لَهُۥ سُوٓءُ عَمَلِهِۦ فَرَءَاهُ حَسَنًا ۖ فَإِنَّ ٱللَّهَ يُضِلُّ مَن يَشَآءُ وَيَهْدِى مَن يَشَآءُ ۖ فَلَا تَذْهَبْ نَفْسُكَ عَلَيْهِمْ حَسَرَٰتٍ ۚ إِنَّ ٱللَّهَ عَلِيمٌۢ بِمَا يَصْنَعُونَ
7. Those who disbelieve, theirs will be a severe torment; and those who believe and do righteous good deeds, theirs will be forgiveness and a great reward. 8. Is he, then, to whom the evil of his deeds is made fairseeming, so that he considers it as good Verily, Allah sends astray whom He wills, and guides whom He wills. So destroy not yourself in sorrow for them. Truly, Allah is the All-Knower of what they do!
Having stated that the ultimate destiny of the followers of Iblis will be the blazing Fire, Allah then tells us that for those who disbelieve there will be a severe punishment. This is because they obeyed the Shaytan and disobeyed Ar-Rahman. And He tells us that those who believed in Allah and His Messengers
(and do righteous good deeds, theirs will be forgiveness) meaning, from whatever sins they did,
and a great reward. for the good deeds that they did. Then Alla0h says:
(Is he, then, to whom the evil of his deeds is made fairseeming, so that he considers it as good) meaning, `such as disbelievers or immoral persons who do evil deeds and believe that they are doing something good, i.e., a person who is like that has been misguided by Allah, so what can you do for him You cannot help him at all.'
(Verily, Allah sends astray whom He wills and guides whom He wills.) means according to His decree.
(So destroy not yourself in sorrow for them. ) means, do not grieve about that, for Allah is Wise in His decree and He leaves astray whomsoever He leaves astray, and He guides whomsoever He guides, and in doing so He has perfect knowledge and wisdom. Allah says:
(Truly, Allah is the All-Knower of what they do!)