Musnad Ahmad 5:531

Abdullah narrated to us, Ubaydullah ibn Umar al-Qawariri narrated to us, Ibn Mahdi narrated to us, from Sufyan, from Zubayd, from Sa'd ibn Ubaydah, from Abu Abd al-Rahman al-Sulami, from Ali, from the Prophet, peace and blessings of Allah be upon him, who said: "There is no obedience to a created being in disobedience to Allah, the Almighty and Majestic."