Riyad as-Salihin, Book 5, Hadith 835 (In-Book)

Abu Hurairah (May Allah be pleased with him) reported: Messenger of Allah said, "Those people who leave a gathering in which they have not remembered Allah, will conclude it as if it has foul odour similar to that of a rotten carcass of a donkey. And it will be a cause of grief to them."[Abu Dawud].

وعن أبى هريرة رضى الله عنه قال‏:‏ قال رسول الله صلى الله عليه وسلم‏:‏ ‏ "‏ما من قوم يقومون من مجلس لا يذكرون الله تعالى فيه، إلا قاموا عن مثل جيفة حمار، وكان لهم حسرة‏" ‏

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