Musnad Ahmad 937:37

Marhum narrated to us, Abu Imran al-Jawni narrated to me, from Abdullah ibn al-Samit, from Abu Dharr, who said: The Messenger of Allah (peace and blessings of Allah be upon him) rode a donkey and had me ride behind him. He said: "O Abu Dharr, what do you think if a severe hunger strikes the people, such that you are unable to rise from your bed to your mosque, what would you do?" I said: Allah and His Messenger know best. He said: "Maintain restraint (ta'affuf)." He said: "O Abu Dharr, what do you think if a severe death strikes the people, such that a house is equivalent to a slave—meaning a grave—what would you do?" I said: Allah and His Messenger know best. He said: "Be patient." He said: "O Abu Dharr, what do you think if the people kill one another, until the stones of al-Zayt are submerged in blood, what would you do?" I said: Allah and His Messenger know best. He said: "Sit in your house and close your door upon yourself." I said: What if I am not left alone? He said: "Then go to those whom you are from, and be among them." I said: Should I take my weapon? He said: "Then you would participate with them in what they are in. But if you fear that the flash of the sword might startle you, then cast the edge of your garment over your face, so that he may return with his sin and your sin."