Bulugh al-Maram
Narrated Abu Bakra (RA): The Prophet (ﷺ) considered Shahadah az-Zur (giving false testimony) among the most serious of major sins. [al-Bukhari and Muslim reported it in a long Hadith].
وَعَنْ أَبِي بَكْرَةَ - رضى الله عنه - { عَنِ النَّبِيِّ - صلى الله عليه وسلم -أَنَّهُ عَدَّ شَهَادَةَ اَلزُّورِ فِ ي 1 أَكْبَرِ اَلْكَبَائِرِ } مُتَّفَقٌ عَلَيْهِ فِي حَدِيث ٍ 2 .
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