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كتاب فضائل أصحاب النبى صلى الله عليه وسلم
62  
Companions of the Prophet
(22)
Chapter: The merits of Al-Hasan and Al-Husain رضي الله عنهما
(22)
باب مَنَاقِبُ الْحَسَنِ وَالْحُسَيْنِ رضى الله عنهما
Sahih al-Bukhari 3747

Narrated Abu Bakra:

I heard the Prophet (ﷺ) talking at the pulpit while Al-Hasan was sitting beside him, and he (i.e. the Prophet ) was once looking at the people and at another time Al-Hasan, and saying, "This son of mine is a Saiyid (i.e. chief) and perhaps Allah will bring about an agreement between two sects of the Muslims through him."

حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا الْمُعْتَمِرُ، قَالَ سَمِعْتُ أَبِي قَالَ، حَدَّثَنَا أَبُو عُثْمَانَ، عَنْ أُسَامَةَ بْنِ زَيْدٍ ـ رضى الله عنهما ـ عَنِ النَّبِيِّ صلى الله عليه وسلم أَنَّهُ كَانَ يَأْخُذُهُ وَالْحَسَنَ وَيَقُولُ ‏ "‏ اللَّهُمَّ إِنِّي أُحِبُّهُمَا فَأَحِبَّهُمَا ‏" ‏‏.‏ أَوْ كَمَا قَالَ‏.‏
Reference : Sahih al-Bukhari 3747
In-book reference : Book 62, Hadith 0
USC-MSA web (English) reference : Vol. 5, Book 57, Hadith 89
  (deprecated numbering scheme)