Riyad as-Salihin, Book 18, Hadith 1553 (In-Book)

Abud-Darda' (May Allah be pleased with him) said: The Messenger of Allah said, "Those who frequently resort to cursing (people) would neither be accepted as witnesses nor as intercessors on the Day of Resurrection."[Muslim].

وعن أبي الدرداء رضي الله عنه قال‏:‏ قال رسول الله صلى الله عليه وسلم ‏:‏ ‏ "‏لا يكون اللعانون شفعاء، ولا شهداء يوم القيامة‏" ‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏‏.‏

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