Sahih al-Bukhari 7142
Sahih al-Bukhari · Book 93: Judgments (Ahkaam) · To listen to and obey the Imam
Narrated Anas bin Malik:
حَدَّثَنَا مُسَدَّدٌ ، حَدَّثَنَا يَحْيَى ، عَنْ شُعْبَةَ ، عَنْ أَبِي التَّيَّاحِ ، عَنْ أَنَسِ بْنِ مَالِكٍ ـ رضى الله عنه ـ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " اسْمَعُوا وَأَطِيعُوا وَإِنِ اسْتُعْمِلَ عَلَيْكُمْ عَبْدٌ حَبَشِيٌّ كَأَنَّ رَأْسَهُ زَبِيبَةٌ " .
Allah's Messenger (ﷺ) said, "You should listen to and obey, your ruler even if he was an Ethiopian (black) slave whose head looks like a raisin."