Sahih Bukhari
Judgments (Ahkaam)
Volume: 009 / Book Number: 089 / Hadith Number: 251
Narrated Abu Huraira:
Allah's Apostle said, "Whoever obeys me, obeys Allah, and whoever disobeys me, disobeys Allah, and whoever obeys the ruler I appoint, obeys me, and whoever disobeys him, disobeys me."