(40) باب الأَمْرِ بِوَضْعِ الْيَدِ عَلَى فِي الْمُتَلاَعِنَيْنِ عِنْدَ الْخَامِسَةِ
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
English translation: Vol. 4, Book 27, Hadith 3502