Anas ibn Mālik (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "Listen and obey, even if an Abyssinian slave, whose head is like a raisin, was appointed a ruler over you.”
Listen to your rulers and be obedient to them even if an Abyssinian slave whose head is like a raisin is appointed to be your leader. The comparison of his head to a raisin denotes physical description, because the hair of Abyssinians is not like the hair of the Arabs. Abyssinian hair is curly, with their curls resembling raisins. This is an emphasis on the fact that the mentioned ruler is of pure Abyssinian descent. "Was appointed a ruler over you" indicates that the order to listen and obey includes the deputy of the supreme leader as well as the leader himself. If it happens that a leader overcame the people and took control of them and he is not an Arab, rather, he is an Abyssinian slave, then it is our duty to listen and obey him. This Hadīth is proof that it is obligatory to be obedient to the rulers, except if they order us to disobey Allah, because obedience to them ensures stability and security, and prevents chaos and the pursuit of personal inclinations and desires. If someone disobeys the rulers in a matter where it is obligatory to obey them, then this leads to chaos and the bias of each individual to his own opinion. Consequently, security is compromised, state matters fall into disorder, and trials and tribulations become widespread.