Musnad Abu Ya'la al-Mawsili 161:21

Ishaq narrated to us, Hisham bin Yusuf narrated to us, from Umayyah bin Shibl, from al-Hakam bin Aban, from Ikrimah, from Abu Hurayrah, who said: I heard the Messenger of Allah (peace and blessings of Allah be upon him) narrating about Musa (peace be upon him) upon the pulpit. He said: It occurred to his soul: "Does Allah, the Mighty and Majestic, sleep?" So Allah sent an angel to him, who kept him awake for three [days/nights]. Then He gave him two glass vials, one in each hand, and commanded him to guard them. He said: He would begin to sleep, and his hands would almost meet. Then he would wake up and restrain one of them against the other, until he fell into a sleep, and his hands struck together, and the two glass vials broke. He said: Allah struck a parable for him that if Allah, the Mighty and Majestic, were to sleep, the heavens and the earth would not be held together.