Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
muslim:2871b – Abū Bakr b. Abū Shaybah And Muḥammad b. al-Muthanná Waʾabū Bakr b. Nāfiʿ > ʿAbd al-Raḥman Yaʿnūn Ibn Mahdī > Sufyān from his father > Khaythamah > al-Barāʾ

"Allah keeps those who believe steadfast with firm word in this world and the Hereafter" was revealed in connection with the torment of the grave.  

مسلم:٢٨٧١b – حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ وَمُحَمَّدُ بْنُ الْمُثَنَّى وَأَبُو بَكْرِ بْنُ نَافِعٍ قَالُوا حَدَّثَنَا عَبْدُ الرَّحْمَنِ يَعْنُونَ ابْنَ مَهْدِيٍّ عَنْ سُفْيَانَ عَنْ أَبِيهِ عَنْ خَيْثَمَةَ عَنِ الْبَرَاءِ بْنِ عَازِبٍ { يُثَبِّتُ اللَّهُ الَّذِينَ آمَنُوا بِالْقَوْلِ الثَّابِتِ فِي الْحَيَاةِ الدُّنْيَا وَفِي الآخِرَةِ} قَالَ

نَزَلَتْ فِي عَذَابِ الْقَبْرِ  

See similar narrations below:

Collected by Aḥmad, Nasāʾī's Kubrá
ahmad:18121 – ʿAffān > Shuʿbah > al-Ḥakam > Ibn Abū Laylá > Kaʿb b. ʿUjrah

[Machine] It landed on me.  

أحمد:١٨١٢١ – حَدَّثَنَا عَفَّانُ حَدَّثَنَا شُعْبَةُ أَخْبَرَنَا الْحَكَمُ عَنِ ابْنِ أَبِي لَيْلَى عَنْ كَعْبِ بْنِ عُجْرَةَ قَالَ

نَزَلَتْ فِيَّ  

nasai-kubra:11202 – Isḥāq b. Manṣūr > ʿAbd al-Raḥman > Sufyān from his father > Khaythamah

"Allah keeps those who believe steadfast with firm word in this world and the Hereafter" was revealed in connection with the torment of the grave. (Using translation from Muslim 2871b)  

الكبرى للنسائي:١١٢٠٢ – أَخْبَرَنَا إِسْحَاقُ بْنُ مَنْصُورٍ أَخْبَرَنَا عَبْدُ الرَّحْمَنِ عَنْ سُفْيَانَ عَنْ أَبِيهِ عَنْ خَيْثَمَةَ عَنِ الْبَرَاءِ بْنِ عَازِبٍ {يُثَبِّتُ اللهُ الَّذِينَ آمَنُوا بِالْقَوْلِ الثَّابِتِ فِي الْحَيَاةِ الدُّنْيَا} [إبراهيم 27] قَالَ

«نَزَلَتْ فِي عَذَابِ الْقَبْرِ»