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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(1d)
"Indeed he (Muḥammad pbuh) did see of the Greatest Signs of his Lord (Allah)." (V.53:18)
(1م2)
Sahih al-Bukhari 4858

Narrated `Abdullah:

(regarding the revelation) Truly he (Muhammad) did see of the signs of his Lord; the Greatest!' (53.18) The Prophet (ﷺ) saw a green screen covering the horizon.

حَدَّثَنَا قَبِيصَةُ، حَدَّثَنَا سُفْيَانُ، عَنِ الأَعْمَشِ، عَنْ إِبْرَاهِيمَ، عَنْ عَلْقَمَةَ، عَنْ عَبْدِ اللَّهِ ـ رضى الله عنه – ‏{‏لَقَدْ رَأَى مِنْ آيَاتِ رَبِّهِ الْكُبْرَى‏}‏ قَالَ رَأَى رَفْرَفًا أَخْضَرَ قَدْ سَدَّ الأُفُقَ‏.‏
Reference : Sahih al-Bukhari 4858
In-book reference : Book 65, Hadith 379
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 381
  (deprecated numbering scheme)