Hadith 3472
Chapter 40: The Command To Place The Hand Over The Mouth Of The Two Who Are Engaging In Li'an When They Utter Th - كتاب الطلاق
أَخْبَرَنَا عَلِيُّ بْنُ مَيْمُونٍ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ عَاصِمِ بْنِ كُلَيْبٍ، عَنْ أَبِيهِ، عَنِ ابْنِ عَبَّاسٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم أَمَرَ رَجُلاً حِينَ أَمَرَ الْمُتَلاَعِنَيْنِ أَنْ يَتَلاَعَنَا أَنْ يَضَعَ يَدَهُ عِنْدَ الْخَامِسَةِ عَلَى فِيهِ وَقَالَ " إِنَّهَا مُوجِبَةٌ " .
It was narrated from Ibn 'Abbas:
"When the Prophet commanded the two who were engaging in Li'an to utter the fifth oath, he commanded a man to place his hand over his mouth, and he said: "It will inevitably bring the punishment upon the liar.""
Reference : Sunan an-Nasa'i 3472
In-book reference : Book 27, Hadith 84