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كتاب التوحيد
97  
Oneness, Uniqueness of Allah (Tawheed)
(4)
Chapter: “(He Alone is) the All-Knower of the Unseen, and He reveals to none His Unseen.”
(4)
Sahih al-Bukhari 7380

Narrated Masruq:

`Aisha said, "If anyone tells you that Muhammad has seen his Lord, he is a liar, for Allah says: 'No vision can grasp Him.' (6.103) And if anyone tells you that Muhammad has seen the Unseen, he is a liar, for Allah says: "None has the knowledge of the Unseen but Allah."

حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ، حَدَّثَنَا سُفْيَانُ، عَنْ إِسْمَاعِيلَ، عَنِ الشَّعْبِيِّ، عَنْ مَسْرُوقٍ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ مَنْ حَدَّثَكَ أَنَّ مُحَمَّدًا صلى الله عليه وسلم رَأَى رَبَّهُ فَقَدْ كَذَبَ وَهْوَ يَقُولُ ‏{‏لاَ تُدْرِكُهُ الأَبْصَارُ‏}‏ وَمَنْ حَدَّثَكَ أَنَّهُ يَعْلَمُ الْغَيْبَ فَقَدْ كَذَبَ، وَهْوَ يَقُولُ لاَ يَعْلَمُ الْغَيْبَ إِلاَّ اللَّهُ‏.‏
Reference : Sahih al-Bukhari 7380
In-book reference : Book 97, Hadith 10
USC-MSA web (English) reference : Vol. 9, Book 93, Hadith 477
  (deprecated numbering scheme)