Sahih Bukhari
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
Volume: 005 / Book Number: 059 / Hadith Number: 435
Narrated Sulaiman bin Surd:
On the day of Al-Ahzab (i.e. clans) the Prophet said, (After this battle) we will go to attack them(i.e. the infidels) and they will not come to attack us."