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كتاب التوحيد
97  
Oneness, Uniqueness of Allah (Tawheed)
Sahih al-Bukhari 7421

Narrated Anas bin Malik:

The Verse of Al-Hijab (veiling of women) was revealed in connection with Zainab bint Jahsh. (On the day of her marriage with him) the Prophet (ﷺ) gave a wedding banquet with bread and meat; and she used to boast before other wives of the Prophet (ﷺ) and used to say, "Allah married me (to the Prophet (ﷺ) in the Heavens."

حَدَّثَنَا خَلاَّدُ بْنُ يَحْيَى، حَدَّثَنَا عِيسَى بْنُ طَهْمَانَ، قَالَ سَمِعْتُ أَنَسَ بْنَ مَالِكٍ ـ رضى الله عنه ـ يَقُولُ نَزَلَتْ آيَةُ الْحِجَابِ فِي زَيْنَبَ بِنْتِ جَحْشٍ وَأَطْعَمَ عَلَيْهَا يَوْمَئِذٍ خُبْزًا وَلَحْمًا وَكَانَتْ تَفْخَرُ عَلَى نِسَاءِ النَّبِيِّ صلى الله عليه وسلم وَكَانَتْ تَقُولُ إِنَّ اللَّهَ أَنْكَحَنِي فِي السَّمَاءِ‏.‏
Reference : Sahih al-Bukhari 7421
In-book reference : Book 97, Hadith 49
USC-MSA web (English) reference : Vol. 9, Book 93, Hadith 517
  (deprecated numbering scheme)