Muhammad bin 'Abdullah bin 'Abdul Hakam محمد بن عبد الله بن عبد الحكم · The Book of al-Bay'ah

"The Messenger of Allah said: 'Whoever obeys me, obeys Allah, and whoever disobeys me, disobeys Allah. Whoever obeys my governor (Amir), he has obeyed me, and whoever disobeys my governor, he has disobeyed me."'