The Book of Virtue, Enjoining Good Manners, and Joining of the Ties of Kinship
Ṣaḥīḥ Muslim 2598c
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إِنَّ اللَّعَّانِينَ لاَ يَكُونُونَ شُهَدَاءَ وَلاَ شُفَعَاءَ يَوْمَ الْقِيَامَةِ
inna al-laʿʿānīna lā yakūnūna shuhadāʾa walā shufaʿāʾa yawma al-qiyāmah
Transliteration generated from the Arabic vowel marks
The full narration
Umm Darda' reported on the authority of Abu Darda' as saying:I heard Allah's Messenger (ﷺ) as saying: The invoker of curse would neither be witness nor intercessor on the Day of Resurrection
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Ṣaḥīḥ Muslim · 2598c
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