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كتاب الجنائز
23  
Funerals (Al-Janaa'iz)
(96)
Chapter: The graves of the Prophet (pbuh), Abu Bakr, and Umar Radiyallahu Anhu
(96)
باب مَا جَاءَ فِي قَبْرِ النَّبِيِّ صلى الله عليه وسلم وَأَبِي بَكْرٍ وَعُمَرَ ـ رضى الله عنهما
Sahih al-Bukhari 1390c

Narrated `Urwa:

When the wall fell on them (i.e. graves) during the caliphate of Al-Walid bin `Abdul Malik, the people started repairing it, and a foot appeared to them. The people got scared and thought that it was the foot of the Prophet. No one could be found who could tell them about it till I (`Urwa) said to them, "By Allah, this is not the foot of the Prophet (ﷺ) but it is the foot of `Umar."

حَدَّثَنَا فَرْوَةُ، حَدَّثَنَا عَلِيٌّ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، لَمَّا سَقَطَ عَلَيْهِمُ الْحَائِطُ فِي زَمَانِ الْوَلِيدِ بْنِ عَبْدِ الْمَلِكِ أَخَذُوا فِي بِنَائِهِ، فَبَدَتْ لَهُمْ قَدَمٌ فَفَزِعُوا، وَظَنُّوا أَنَّهَا قَدَمُ النَّبِيِّ صلى الله عليه وسلم فَمَا وَجَدُوا أَحَدًا يَعْلَمُ ذَلِكَ حَتَّى قَالَ لَهُمْ عُرْوَةُ لاَ وَاللَّهِ مَا هِيَ قَدَمُ النَّبِيِّ صلى الله عليه وسلم مَا هِيَ إِلاَّ قَدَمُ عُمَرَ ـ رضى الله عنه ـ‏.‏
Reference : Sahih al-Bukhari 1390c
In-book reference : Book 23, Hadith 144
USC-MSA web (English) reference : Vol. 2, Book 23, Hadith 474
  (deprecated numbering scheme)