Muhammad bin Sirin (may Allah have mercy on him) narrates that one of Sayyiduna Imran bin Husayn (may Allah be pleased with him) and Sayyiduna al-Hakam al-Ghifari (may Allah be pleased with him), and he thinks it was Imran (may Allah be pleased with him), used to narrate this hadith that the Messenger of Allah (peace and blessings be upon him) said: "There is no obedience to anyone in disobedience to Allah." The narrator said: He used to long to meet the other because of this hadith. Then they met, and he asked: Did you hear the Messenger of Allah (peace and blessings be upon him) saying: "There is no obedience to anyone in disobedience to Allah"? The other said: Yes. So he said: Allahu akbar, Allahu akbar (Allah is the Greatest, Allah is the Greatest), or as he said.
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 3147