Sahih Muslim 179
Sahih Muslim · Book 1: The Book of Faith · The saying of the Prophet (saws): "Allah does not sleep" and "His veil is light, and if he were to remove it, the splendour of his face would burn all of his creation, as far as hs sght reaches".
Abu Musa reported:
حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى ، وَابْنُ، بَشَّارٍ قَالاَ حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ ، قَالَ حَدَّثَنِي شُعْبَةُ ، عَنْ عَمْرِو بْنِ مُرَّةَ ، عَنْ أَبِي عُبَيْدَةَ ، عَنْ أَبِي مُوسَى ، قَالَ قَامَ فِينَا رَسُولُ اللَّهِ صلى الله عليه وسلم بِأَرْبَعٍ " إِنَّ اللَّهَ لاَ يَنَامُ وَلاَ يَنْبَغِي لَهُ أَنْ يَنَامَ يَرْفَعُ الْقِسْطَ وَيَخْفِضُهُ وَيُرْفَعُ إِلَيْهِ عَمَلُ النَّهَارِ بِاللَّيْلِ وَعَمَلُ اللَّيْلِ بِالنَّهَارِ " .
The Messenger of Allah (ﷺ) was standing amongst us and (he said) four (things): Verily Allah does 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.