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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(5)
The Statement of Allah the Most High: "...When they gave their Bai'a (pledge) to you (O Muḥammad pbuh) under the tree..." (V.48:18)
(5)
Sahih al-Bukhari 4840

Narrated Jabir:

We were one thousand and four hundred on the Day of Al-Hudaibiya.

حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا سُفْيَانُ، عَنْ عَمْرٍو، عَنْ جَابِرٍ، قَالَ كُنَّا يَوْمَ الْحُدَيْبِيَةِ أَلْفًا وَأَرْبَعَمِائَةٍ‏.‏
Reference : Sahih al-Bukhari 4840
In-book reference : Book 65, Hadith 361
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 364
  (deprecated numbering scheme)