Allah says in the Qur’an:

﴿وَهُوَ الَّذِي جَعَلَ لَكُمُ اللَّيْلَ لِتَسْكُنُوا فِيهِ وَالنَّهَارَ مُبْصِرًا ۚ إِنَّ فِي ذَٰلِكَ لَآيَاتٍ لِقَوْمٍ يَسْمَعُونَ﴾

(Surah Yunus, 10:67)

Translation:

“And He it is who made the night for you to rest in, and the day for sight. Indeed in that are signs for people who listen.”

The Qur’an describes sleep as a form of rest and restoration, and emphasizes the cyclical nature of night and day.

Modern science confirms:

• Sleep is essential for physical restoration (muscle repair, tissue growth)

• Sleep supports memory consolidation and cognitive function

• The circadian rhythm, regulated by light and darkness, governs sleep-wake cycles

Even more remarkably, the Qur’an describes a state resembling death during sleep:

﴿وَتُسَبِّحُ اللَّيْلَ طَوِيلًا وَتُسَبِّحُ النَّهَارَ عَشِيًّا﴾

(Interpretation: Sleep is like a minor “death” from which we awaken rejuvenated)

For people in the 7th century, understanding the scientific and restorative role of sleep was not known, yet the Qur’an presents it as a natural sign of God’s wisdom.