Quran 74:31 from Surah Al-Muddaththir on Divine Marvels.
وَمَا جَعَلۡنَآ أَصۡحَٰبَ ٱلنَّارِ إِلَّا مَلَٰٓئِكَةٗۖ وَمَا جَعَلۡنَا عِدَّتَهُمۡ إِلَّا فِتۡنَةٗ لِّلَّذِينَ كَفَرُواْ لِيَسۡتَيۡقِنَ ٱلَّذِينَ أُوتُواْ ٱلۡكِتَٰبَ وَيَزۡدَادَ ٱلَّذِينَ ءَامَنُوٓاْ إِيمَٰنٗا وَلَا يَرۡتَابَ ٱلَّذِينَ أُوتُواْ ٱلۡكِتَٰبَ وَٱلۡمُؤۡمِنُونَ وَلِيَقُولَ ٱلَّذِينَ فِي قُلُوبِهِم مَّرَضٞ وَٱلۡكَٰفِرُونَ مَاذَآ أَرَادَ ٱللَّهُ بِهَٰذَا مَثَلٗاۚ كَذَٰلِكَ يُضِلُّ ٱللَّهُ مَن يَشَآءُ وَيَهۡدِي مَن يَشَآءُۚ وَمَا يَعۡلَمُ جُنُودَ رَبِّكَ إِلَّا هُوَۚ وَمَا هِيَ إِلَّا ذِكۡرَىٰ لِلۡبَشَرِ
English translation: And not We have made keepers (of) the Fire except Angels And not We have made their number except (as) a trial for those who disbelieve that may be certain those who were given the Scripture and may increase those who believe (in) faith and not may doubt those who were given the Scripture and the believers and that may say those in their hearts (is) a disease and the disbelievers What (does) intend Allah by this example Thus does let go astray Allah whom He wills and guides whom He wills And none knows (the) hosts (of) your Lord except Him And not it (is) but a reminder to (the) human beings
Transliteration: wama ja'alna ashaba al-nari illa malaikatan wama ja'alna iddatahum illa fit'natan lilladhina kafaru liyastayqina alladhina utu al-kitaba wayazdada alladhina amanu imanan wala yartaba alladhina utu al-kitaba wal-mu'minuna waliyaqula alladhina fi qulubihim maradun wal-kafiruna madha arada al-lahu bihadha mathalan kadhalika yudillu al-lahu man yashau wayahdi man yashau wama ya'lamu junuda rabbika illa huwa wama hiya illa dhik'ra lil'bashari