Sahih Muslim
The Book on Government (Kitab Al-Imara)
Book Number: 020 / Hadith Number: 4473
It has been narrarted on the authority of Abu Huraira that the Messenger of Allah (may peace be upon him) said: People are subservient to the Quraish: the Muslims among them being subservient to the Muslims among them, and the disbelievers among the people being subservient to the disbelievers among them.