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 ‏"‏‏.‏

Al-Bara' bin `Azib said (through another chain of sub-narrators): "On the day of Quraiza's (siege), Allah's Messenger (PBUH) said to Hassan bin Thabit, 'Abuse them (with your poems), and Jibril is with you.'" Translation Not Available

Book Ref: Sahih Bukhari Book 64 Hadith 4124
Web Ref:  Sahih Bukhari Vol 1 Book 59 Hadith 449