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كتاب الشهادات
52  
Witnesses
(21)
Chapter: If someone claims something or accuses somebody he should be given respite to get evidence
(21)
باب إِذَا ادَّعَى أَوْ قَذَفَ فَلَهُ أَنْ يَلْتَمِسَ الْبَيِّنَةَ، وَيَنْطَلِقَ لِطَلَبِ الْبَيِّنَةِ
Sahih al-Bukhari 2671

Narrated Ibn `Abbas:

Hilal bin Umaiya accused his wife before the Prophet (ﷺ) of committing illegal sexual intercourse with Sharik bin Sahma.' The Prophet (ﷺ) said, "Produce a proof, or else you would get the legal punishment (by being lashed) on your back." Hilal said, "O Allah's Messenger (ﷺ)! If anyone of us saw another man over his wife, would he go to search for a proof." The Prophet (ﷺ) went on saying, "Produce a proof or else you would get the legal punishment (by being lashed) on your back." The Prophet (ﷺ) then mentioned the narration of Lian (as in the Holy Book). (Surat-al-Nur: 24)

حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا ابْنُ أَبِي عَدِيٍّ، عَنْ هِشَامٍ، حَدَّثَنَا عِكْرِمَةُ، عَنِ ابْنِ عَبَّاسٍ ـ رضى الله عنهما ـ أَنَّ هِلاَلَ بْنَ أُمَيَّةَ، قَذَفَ امْرَأَتَهُ عِنْدَ النَّبِيِّ صلى الله عليه وسلم بِشَرِيكِ بْنِ سَحْمَاءَ، فَقَالَ النَّبِيُّ صلى الله عليه وسلم ‏"‏ الْبَيِّنَةُ أَوْ حَدٌّ فِي ظَهْرِكَ ‏"‏‏.‏ فَقَالَ يَا رَسُولَ اللَّهِ إِذَا رَأَى أَحَدُنَا عَلَى امْرَأَتِهِ رَجُلاً يَنْطَلِقُ يَلْتَمِسُ الْبَيِّنَةَ فَجَعَلَ يَقُولُ ‏"‏ الْبَيِّنَةَ وَإِلاَّ حَدٌّ فِي ظَهْرِكَ ‏"‏‏.‏ فَذَكَرَ حَدِيثَ اللِّعَانِ‏.‏
Reference : Sahih al-Bukhari 2671
In-book reference : Book 52, Hadith 33
USC-MSA web (English) reference : Vol. 3, Book 48, Hadith 837
  (deprecated numbering scheme)