Riyad as-Salihin, Book 18, Hadith 1766 (In-Book)

Abu Hurairah (May Allah be pleased with him) said: The Messenger of Allah said, "It is much better for one of you to sit on a live coal, which will burn his clothes and get to his skin than to sit on a grave."[Muslim].

عن أبي هريرة رضي الله عنه قال‏:‏ قال رسول الله صلى الله عليه وسلم ‏:‏‏ "‏ لأن يجلس أحدكم على جمرة، فتحرق ثيابه، فتخلص على جلده خير له من أن يجلس على قبر‏" ‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏

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