Sahih al-Bukhari 1376
Sahih al-Bukhari · Book 23: Funerals (Al-Janaa'iz) · To seek refuge from the punishment in the grave
Narrated Musa bin `Uqba:
حَدَّثَنَا مُعَلًّى ، حَدَّثَنَا وُهَيْبٌ ، عَنْ مُوسَى بْنِ عُقْبَةَ ، قَالَ حَدَّثَتْنِي ابْنَةُ خَالِدِ بْنِ سَعِيدِ بْنِ الْعَاصِ ، أَنَّهَا سَمِعَتِ النَّبِيَّ صلى الله عليه وسلم وَهُوَ يَتَعَوَّذُ مِنْ عَذَابِ الْقَبْرِ.
(From the daughter of Khalid bin Sa id bin Al-`Asi) who said that she had heard the Prophet (ﷺ) seeking refuge with Allah from the punishment in the grave.