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ٱلَّذِينَ ءَامَنُواْ وَتَطۡمَئِنُّ قُلُوبُهُم بِذِكۡرِ ٱللَّهِۗ أَلَا بِذِكۡرِ ٱللَّهِ تَطۡمَئِنُّ ٱلۡقُلُوبُ
those who believe and whose hearts find tranquility in the remembrance of Allah, for indeed in the remembrance of Allah do hearts find tranquility.