The word(s) "نكفر" appears in 4 verse(s) in Quran.

(1) إِن تَجْتَنِبُوا كَبَائِرَ مَا تُنْهَوْنَ عَنْهُ نُكَفِّرْ عَنكُمْ سَيِّئَاتِكُمْ وَنُدْخِلْكُم مُّدْخَلًا كَرِيمًا

(سورة النساء, An-Nisaa, Chapter #4, Verse #31)
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(2) إِنَّ الَّذِينَ يَكْفُرُونَ بِاللَّهِ وَرُسُلِهِ وَيُرِيدُونَ أَن يُفَرِّقُوا بَيْنَ اللَّهِ وَرُسُلِهِ وَيَقُولُونَ نُؤْمِنُ بِبَعْضٍ وَنَكْفُرُ بِبَعْضٍ وَيُرِيدُونَ أَن يَتَّخِذُوا بَيْنَ ذَ‌ٰلِكَ سَبِيلًا

(سورة النساء, An-Nisaa, Chapter #4, Verse #150)
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(3) وَالَّذِينَ آمَنُوا وَعَمِلُوا الصَّالِحَاتِ لَنُكَفِّرَنَّ عَنْهُمْ سَيِّئَاتِهِمْ وَلَنَجْزِيَنَّهُمْ أَحْسَنَ الَّذِي كَانُوا يَعْمَلُونَ

(سورة العنكبوت, Al-Ankaboot, Chapter #29, Verse #7)
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(4) وَقَالَ الَّذِينَ اسْتُضْعِفُوا لِلَّذِينَ اسْتَكْبَرُوا بَلْ مَكْرُ اللَّيْلِ وَالنَّهَارِ إِذْ تَأْمُرُونَنَا أَن نَّكْفُرَ بِاللَّهِ وَنَجْعَلَ لَهُ أَندَادًا ۚ وَأَسَرُّوا النَّدَامَةَ لَمَّا رَأَوُا الْعَذَابَ وَجَعَلْنَا الْأَغْلَالَ فِي أَعْنَاقِ الَّذِينَ كَفَرُوا ۚ هَلْ يُجْزَوْنَ إِلَّا مَا كَانُوا يَعْمَلُونَ

(سورة سبإ, Saba, Chapter #34, Verse #33)
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