Sahih Bukhari Volume 4, Book 56, Hadith Number 715.

Narated By Abu Huraira : The Prophet said, “The tribes of Quraish, Al-Ansar, Juhaina, Muzaina, Aslam, Ghifar and Ashja’ are my helpers, and they have no protector (i.e. Master) except Allah and His Apostle.”