كتاب المغازى
64  
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
(30)
Chapter: The return of the Prophet (saws) from Ahzab and his going out to Bani Quraiza
(30)
بَابُ مَرْجَعِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مِنَ الأَحْزَابِ وَمَخْرَجِهِ إِلَى بَنِي قُرَيْظَةَ وَمُحَاصَرَتِهِ إِيَّاهُمْ
Sahih al-Bukhari 4124
Al-Bara' bin `Azib said (through another chain of sub-narrators):
"On the day of Quraiza's (siege), Allah's Messenger (ﷺ) said to Hassan bin Thabit, 'Abuse them (with your poems), and Jibril is with you.'"
وَزَادَ إِبْرَاهِيمُ بْنُ طَهْمَانَ عَنِ الشَّيْبَانِيِّ، عَنْ عَدِيِّ بْنِ ثَابِتٍ، عَنِ الْبَرَاءِ بْنِ عَازِبٍ، قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَوْمَ قُرَيْظَةَ لِحَسَّانَ بْنِ ثَابِتٍ ‏ "‏ اهْجُ الْمُشْرِكِينَ، فَإِنَّ جِبْرِيلَ مَعَكَ ‏"‏‏.‏
Reference : Sahih al-Bukhari 4124
In-book reference : Book 64, Hadith 168
USC-MSA web (English) reference : Vol. 1, Book 59, Hadith 449
  (deprecated numbering scheme)