Sunan Abi Dawud

Sunan Abi Dawud 2255

Regarding Li'an (Mutual Cursing)
Arabic hadith text
حَدَّثَنَا مَخْلَدُ بْنُ خَالِدٍ الشَّعِيرِيُّ، حَدَّثَنَا سُفْيَانُ، عَنْ عَاصِمِ بْنِ كُلَيْبٍ، عَنْ أَبِيهِ، عَنِ ابْنِ عَبَّاسٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم أَمَرَ رَجُلاً حِينَأَمَرَ الْمُتَلاَعِنَيْنِ أَنْ يَتَلاَعَنَا أَنْ يَضَعَ يَدَهُ عَلَى فِيهِ عِنْدَ الْخَامِسَةِ يَقُولُ إِنَّهَا مُوجِبَةٌ ‏.‏
Translation
Narrated Abdullah ibn Abbas

That the Prophet (ﷺ) commanded a man, when he commanded the two who were engaging in mutual imprecation (li'an) to invoke curses upon each other, to place his hand over his mouth at the fifth [oath], saying, 'Indeed, it is the one that brings the [divine] obligation [of punishment].'