The Book of Funerals
21/114. Chapter:
The Punishment of The Grave
Sunan an-Nasai
أَخْبَرَنَا إِسْحَاقُ بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا عَبْدُ الرَّحْمَنِ، عَنْ سُفْيَانَ، عَنْ أَبِيهِ، عَنْ خَيْثَمَةَ، عَنِ الْبَرَاءِ، قَالَ { يُثَبِّتُ اللَّهُ الَّذِينَ آمَنُوا بِالْقَوْلِ الثَّابِتِ فِي الْحَيَاةِ الدُّنْيَا وَفِي الآخِرَةِ } قَالَ نَزَلَتْ فِي عَذَابِ الْقَبْرِ .
It was narrated that: Al-Bara said about Allah will keep firm those who believe, with the word that stands firm in this world and in the Hereafter "It was revealed concerning the torment of the grave.
Reference : Sunan an-Nasa'i 2056In-book reference : Book 21, Hadith 239English translation : Vol. 3, Book 21, Hadith 2058