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

(1) مَن كَفَرَ بِاللَّهِ مِن بَعْدِ إِيمَانِهِ إِلَّا مَنْ أُكْرِهَ وَقَلْبُهُ مُطْمَئِنٌّ بِالْإِيمَانِ وَلَـٰكِن مَّن شَرَحَ بِالْكُفْرِ صَدْرًا فَعَلَيْهِمْ غَضَبٌ مِّنَ اللَّهِ وَلَهُمْ عَذَابٌ عَظِيمٌ

(سورة النحل, An-Nahl, Chapter #16, Verse #106)
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(2) وَضَرَبَ اللَّهُ مَثَلًا قَرْيَةً كَانَتْ آمِنَةً مُّطْمَئِنَّةً يَأْتِيهَا رِزْقُهَا رَغَدًا مِّن كُلِّ مَكَانٍ فَكَفَرَتْ بِأَنْعُمِ اللَّهِ فَأَذَاقَهَا اللَّهُ لِبَاسَ الْجُوعِ وَالْخَوْفِ بِمَا كَانُوا يَصْنَعُونَ

(سورة النحل, An-Nahl, Chapter #16, Verse #112)
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(3) قُل لَّوْ كَانَ فِي الْأَرْضِ مَلَائِكَةٌ يَمْشُونَ مُطْمَئِنِّينَ لَنَزَّلْنَا عَلَيْهِم مِّنَ السَّمَاءِ مَلَكًا رَّسُولًا

(سورة الإسراء, Al-Israa, Chapter #17, Verse #95)
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(4) يَا أَيَّتُهَا النَّفْسُ الْمُطْمَئِنَّةُ

(سورة الفجر, Al-Fajr, Chapter #89, Verse #27)
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