﴿الَّذِينَ آمَنُوا وَتَطْمَئِنُّ قُلُوبُهُم بِذِكْرِ اللَّهِ ۗ أَلَا بِذِكْرِ اللَّهِ تَطْمَئِنُّ الْقُلُوبُ﴾
"Those who believe and whose hearts find rest in the remembrance of Allah. Verily, in the remembrance of Allah do hearts find rest."
— Surah Ar-Ra'd (13:28)