Virtues and Merits of the Prophet (pbuh) and his Companions

Bukhari :: Book 4 :: Volume 56 :: Hadith 715

Narrated 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."