Musnad Ahmad 5:162

Muhammad ibn Ja‘far narrated to us, Shu‘bah narrated to us, from Zubayd al-Yamani, from Sa‘d ibn ‘Ubaydah, from Abu ‘Abd al-Rahman, from ‘Ali, that the Messenger of Allah (peace and blessings of Allah be upon him) sent an army and appointed a man over them. He (the commander) kindled a fire and said, "Enter it." Some people wanted to enter it, while others said, "We only fled from it." This was mentioned to the Messenger of Allah (peace and blessings of Allah be upon him), and he said to those who wanted to enter it, "If you had entered it, you would not have ceased to be in it until the Day of Resurrection." He said a good word to the others and said, "There is no obedience in disobedience to Allah; obedience is only in what is good."