It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: Angels of the night and angels of the day take turns among you, and they gather at the times of Fajr and Asr prayers. Then those angels who have stayed among you ascend to the heavens. Although Allah knows everything, He asks them: "In what state did you leave My servants?" They say: "When we left them, they were praying, and when we came to them, they were praying as well."