Quran says:

وَيَسْأَلُونَكَ عَنِ ٱلرُّوحِ قُلِ ٱلرُّوحُ مِنْ أَمْرِ رَبِّى وَمَآ أُوتِيتُم مِّنَ ٱلْعِلْمِ إِلاَّ قَلِيلاً

They ask you (O Muhammad, concerning the spirit; say: ‘the spirit is one of the things, the knowledge of which is only with my Lord. And of knowledge, you (mankind) have been given only a little’.” (Holy Qur’an: 17: 85).

وَلَقَدْ ذَرَأْنَا لِجَهَنَّمَ كَثِيراً مِّنَ ٱلْجِنِّ وَٱلإِنْسِ لَهُمْ قُلُوبٌ لاَّ يَفْقَهُونَ بِهَا وَلَهُمْ أَعْيُنٌ لاَّ يُبْصِرُونَ بِهَا وَلَهُمْ آذَانٌ لاَّ يَسْمَعُونَ بِهَآ أُوْلَـٰئِكَ كَٱلأَنْعَامِ بَلْ هُمْ أَضَلُّ أُوْلَـٰئِكَ هُمُ ٱلْغَافِلُونَ

Quran says:

“while those who disbelieve enjoy themselves and eat as cattle eat; and the Fire will be their abode” and “And surely, We have created many of the jinn and mankind for Hell.  They have hearts wherewith they understand not, and they have eyes wherewith they see not, and they have ears wherewith they hear not (the truth). They are like cattle, nay even more astray; those!  They are the heedless ones.” (Holy Qur’an: 7:179)