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Surah 24. An-Nur
Ayah 21
21 يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ لَا تَتَّبِعُوا۟ خُطُوَٰتِ ٱلشَّيْطَـٰنِ ۚ وَمَن يَتَّبِعْ خُطُوَٰتِ ٱلشَّيْطَـٰنِ فَإِنَّهُۥ يَأْمُرُ بِٱلْفَحْشَآءِ وَٱلْمُنكَرِ ۚ وَلَوْلَا فَضْلُ ٱللَّهِ عَلَيْكُمْ وَرَحْمَتُهُۥ مَا زَكَىٰ مِنكُم مِّنْ أَحَدٍ أَبَدًا وَلَـٰكِنَّ ٱللَّهَ يُزَكِّى مَن يَشَآءُ ۗ وَٱللَّهُ سَمِيعٌ عَلِيمٌ
[21] O Believers, do not follow in Satan's footsteps, for he will incite to indecency and wickedness any who will follow him. If Allah had not shown His Brace and mercy to you, none of you would have been able to cleanse yourself,18 for it is Allah alone Who cleanses whom He wills, and Allah is All-Hearing, All-Knowing.19
18`Satan' is bent upon involving you in all kinds of pollutions and indecencies: had it not been for the mercy and kindness of Allah Who enables you to differentiate between good and evil and helps you to educate and reform yourselves, you would not have been able to lead a pure and virtuous life on the strength of your own faculties and initiative alone.
19It is Allah's Will alone which decides whom to make pious and virtuous. His decisions are not arbitrary but based on knowledge. He alone knows who is anxious to live a life of virtue and who is attracted towards a life of sin. Allah hears a person's most secret talk, and is aware of everything that passes in his mind. It is on the basis of this direct knowledge that Allah decides whom to bless with piety and virtue and whom to ignore.