Sahih Muslim Book 1, Hadith Number 345.

Chapter : Pertaining to his (Prophet’s) words: He is a Light; how could I see Him?-and his words: I saw the Light.

Abu Musa reported: The Messenger of Allah (peace be upon him) was standing amongst us and (he said) four (things): Verily Allah dock not sleep and it does not befit Him to sleep. He raises the scale and lowers it. The deeds of the day are presented to Him in the night and the deeds of the night in the day.