Riyad as-Salihin, Book 16, Hadith 1436 (In-Book)

Abu Hurairah (May Allah be pleased with him) reported: The Messenger of Allah said, "The Mufarridun have gone ahead." He was asked, "Who are the Mufarridun?" He replied, "Those men and women who frequently celebrate the remembrance of Allah."[Muslim].

وعنه قال‏:‏ قال رسول الله صلى الله عليه وسلم‏:‏ ‏"‏سبق المفردون‏"‏ قالوا‏:‏ وما المفردون يا رسول الله‏؟‏ قال‏:‏ ‏"‏الذاكرون الله كثيرًا والذكرات‏"‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏‏.‏

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