(Furqan) 25 : 47
وَهُوَ الَّذِي جَعَلَ لَكُمُ اللَّيْلَ لِبَاسًا وَالنَّوْمَ سُبَاتًا وَجَعَلَ النَّهَارَ نُشُورًا
And He is the One Who has made the night as clothing for you, sleeps a peaceful rest, and the day as a resurrection.
“Night as clothing for you,” told in verse means that during night one can reduce his/her clothing since light is not present. During sleep, the soul departs while life remains, so one will not feel any discomfort during that time. When one wakes up, the soul will return to the body. That’s why the day is called resurrection. When life and soul departs, death happens as explained in verse 6: 60. See explanation 3: 154; 17: 12 and 24: 58.