Verse 31

وَمَا جَعَلْنَآ أَصْحَـٰبَ ٱلنَّارِ إِلَّا مَلَـٰٓئِكَةً وَمَا جَعَلْنَا عِدَّتَهُمْ إِلَّا فِتْنَةً لِّلَّذِينَ كَفَرُوا۟ لِيَسْتَيْقِنَ ٱلَّذِينَ أُوتُوا۟ ٱلْكِتَـٰبَ وَيَزْدَادَ ٱلَّذِينَ ءَامَنُوٓا۟ إِيمَـٰنًا وَلَا يَرْتَابَ ٱلَّذِينَ أُوتُوا۟ ٱلْكِتَـٰبَ وَٱلْمُؤْمِنُونَ وَلِيَقُولَ ٱلَّذِينَ فِى قُلُوبِهِم مَّرَضٌ وَٱلْكَـٰفِرُونَ مَاذَآ أَرَادَ ٱللَّهُ بِهَـٰذَا مَثَلًا كَذَٰلِكَ يُضِلُّ ٱللَّهُ مَن يَشَآءُ وَيَهْدِى مَن يَشَآءُ وَمَا يَعْلَمُ جُنُودَ رَبِّكَ إِلَّا هُوَ وَمَا هِىَ إِلَّا ذِكْرَىٰ لِلْبَشَرِ

And We appointed angels to be guardians of Hell and We have assigned their number only as a test for the unfaithful, and for the people of the scripture to attain certainty, and for the faithful to increase their faith, and that no doubts may remain for the people of the scripture and the faithful, and as for those who have a disease in their hearts and the unfaithful say, what did God mean by this example? God thus sends astray whomever He wills and guides whomever He wills. And no one knows the armies of your Lord except He and this is only a reminder for all the people.