وَهُوَ الَّذِي جَعَلَ لَكُمُ اللَّيْلَ لِبَاسًا وَالنَّوْمَ سُبَاتًا وَجَعَلَ النَّهَارَ نُشُورًا
Huwal-ladhī ja‘ala lakumul-layla libāsan wan-nawma subātan wa ja‘alan-nahāra nushūrā
And He it is Who made the night a covering for you, and the sleep a rest, and He made the day to rise up again.
(Sūratul Furqān, No.25, Āyat 47)
This verse talks about the system that Allah has created for life in this world. The system is designed to ease life for the human being and is both a blessing and a sign of the greatness of the Designer. Both the night and the day are meant for different purposes and each has a role to play in the success of the human being on earth.
Allah describes the night as a covering, something that hides and protects. It falls over the world like a piece of clothing that keeps away light and energy so that all of creation can relax and recuperate from the toil of the day.
Sleep is a rest for the human being. The word sabat means when things are cut off and is used for stopping work and cutting off activity. That is why the word Sabbath was used to denote the day of Saturday when people would take a holiday from work. During sleep most of the bodily activities stop except necessary activities such as breathing, blood circulation etc. All else takes a break and even the activities that continue become slow and relaxed. The body rejuvenates itself and acquires renewed energy for the next day. Appropriate amount of sleep is necessary for the human being to function well.
The day is for rising up and spreading out. The soul rises into the body again, for sleep is comparative to death. Human beings also rise again and resume their activities. It is a form of rebirth and that is why the Holy Prophet (s) used to say at the time of waking up:
اَلْحَمْدُ للهِ الَّذِ أحْيَانِيِ بَعْدَ مَا أمَاتَنِيْ وَاِلَيْهِ النُّشُوْرِ
All Praise is for Allah who gave us life after death and to Him is the return (Sunan p. 84). The light that spreads as day begins creates new energy and all of creation, including animals and plants begin working again. Each works on the role it plays in the world.
Recite this verse each day to remind you of the beauty of purpose behind the night and day. Don’t become so accustomed to it that it fails to spark a sense of wonder each time it happens. The continuous movement of night and day is a sign of the wisdom of Allah who wishes only good for the human being.
Source: Āyatullāh Nāsir Makārim Shirāzī (editor), Tafsīr-e Namūneh; ‘Allāmah Muhammad Husayn Tabātabā‘ī, Sunan An-Nabi, Kitchener: 2007.