Musannaf Ibn Abi Shaybah

It is narrated from Hazrat Jundub bin Abdullah that he says: I sought permission from Hazrat Hudhaifa (may Allah be pleased with him) three times, but he did not grant me permission, so I turned back. Then suddenly his messenger came to me (and brought me). He (may Allah be pleased with him) asked me: What made you turn back? I replied: I thought that you might be asleep. He said: I do not sleep until I have seen the place where the sun rises. The narrator says: I related this to Muhammad, and he said: More than one of the companions (may Allah be pleased with them) of the Noble Prophet (peace and blessings be upon him) used to do this.