The Book of Oaths and Vows
35/41. Chapter:
Expiation For Vows
Sunan an-Nasai
أَخْبَرَنَا يُونُسُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا ابْنُ وَهْبٍ، قَالَ أَخْبَرَنِي يُونُسُ، عَنِ ابْنِ شِهَابٍ، عَنْ أَبِي سَلَمَةَ، عَنْ عَائِشَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لاَ نَذْرَ فِي مَعْصِيَةٍ وَكَفَّارَتُهُ كَفَّارَةُ الْيَمِينِ " .
It was narrated from 'Aishah that the Messenger of Allah said: "There is no vow to commit an act of disobedience and its expiation is the expiation for an oath."
Reference : Sunan an-Nasa'i 3834In-book reference : Book 35, Hadith 74English translation : Vol. 4, Book 35, Hadith 3865