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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
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"...And the moon has been cleft asunder (the people of Makkah requested Prophet Muḥammad pbuh to show them a miracle, so he showed them the splitting of the moon). And if they see a sign, they turn away..." (V.54:1,2)
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Sahih al-Bukhari 4865

Narrated `Abdullah:

The moon was cleft asunder while we were in the company of the Prophet, and it became two parts. The Prophet (ﷺ) said, Witness, witness (this miracle).

حَدَّثَنَا عَلِيٌّ، حَدَّثَنَا سُفْيَانُ، أَخْبَرَنَا ابْنُ أَبِي نَجِيحٍ، عَنْ مُجَاهِدٍ، عَنْ أَبِي مَعْمَرٍ، عَنْ عَبْدِ اللَّهِ، قَالَ انْشَقَّ الْقَمَرُ وَنَحْنُ مَعَ النَّبِيِّ صلى الله عليه وسلم فَصَارَ فِرْقَتَيْنِ، فَقَالَ لَنَا ‏ "‏ اشْهَدُوا، اشْهَدُوا ‏"‏‏.‏
Reference : Sahih al-Bukhari 4865
In-book reference : Book 65, Hadith 386
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 388
  (deprecated numbering scheme)