Riyad as-Salihin, Book 9, Hadith 1026 (In-Book)

'Uthman bin 'Affan (May Allah be pleased with him) reported: The Messenger of Allah said, "He who performs the Wudu' perfectly (i.e., according to Sunnah), his sins will depart from his body, even from under his nails."[Muslim].

وعن عثمان بن عفان رضي الله عنه قال‏:‏ قال رسول الله صلى الله عليه وسلم‏:‏ ‏ "‏من توضأ فأحسن الوضوء، خرجت خطاياه من جسده حتى تخرج من تحت أظفاره‏" ‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏‏.‏

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