The Messenger of Allah (may Allah bless him and grant him peace) said:
“There are angels which take turns in being with you in the night and other angels in the day and they meet together at the prayers of Fajr and ‘Asr. Then the ones who were with you during the night ascend and Allah asks them – although He knows better than they do – ‘How were My slaves when you left them?’ They say, ‘When we left them they were praying and when we came to them, they were praying.’
[Sahih Al-Bukhari]
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