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كتاب الجنائز
23  
Funerals (Al-Janaa'iz)
(69)
Chapter: Burial at night and Abu Bakr (ra) was buried at night.
(69)
باب الدَّفْنِ بِاللَّيْلِ وَدُفِنَ أَبُو بَكْرٍ ـ رضى الله عنه ـ لَيْلاً
Sahih al-Bukhari 1340

Narrated Ibn `Abbas:

The Prophet (p.b.u.h) offered the funeral prayer of a man one night after he was buried, he and his companions stood up (for the Prayer). He had asked them about him before standing, saying, "Who is this?" They said, "He is so and so and was buried last night." So all of them offered the funeral prayer.

حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا جَرِيرٌ، عَنِ الشَّيْبَانِيِّ، عَنِ الشَّعْبِيِّ، عَنِ ابْنِ عَبَّاسٍ ـ رضى الله عنهما ـ قَالَ صَلَّى النَّبِيُّ صلى الله عليه وسلم عَلَى رَجُلٍ بَعْدَ مَا دُفِنَ بِلَيْلَةٍ قَامَ هُوَ وَأَصْحَابُهُ، وَكَانَ سَأَلَ عَنْهُ فَقَالَ ‏ "‏ مَنْ هَذَا ‏"‏‏.‏ فَقَالُوا فُلاَنٌ، دُفِنَ الْبَارِحَةَ‏.‏ فَصَلَّوْا عَلَيْهِ‏.‏
Reference : Sahih al-Bukhari 1340
In-book reference : Book 23, Hadith 95
USC-MSA web (English) reference : Vol. 2, Book 23, Hadith 424
  (deprecated numbering scheme)