The Book of Divorce
18/3. Chapter:
Expiation must be offered by one who declares his wife to be unlawful for him but does not intend divorce thereby
Sahih Muslim
وَحَدَّثَنَا زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا إِسْمَاعِيلُ بْنُ إِبْرَاهِيمَ، عَنْ هِشَامٍ، - يَعْنِي الدَّسْتَوَائِيَّ - قَالَ كَتَبَ إِلَىَّ يَحْيَى بْنُ أَبِي كَثِيرٍ يُحَدِّثُ عَنْ يَعْلَى بْنِ حَكِيمٍ عَنْ سَعِيدِ بْنِ جُبَيْرٍ عَنِ ابْنِ عَبَّاسٍ أَنَّهُ كَانَ يَقُولُ فِي الْحَرَامِ يَمِينٌ يُكَفِّرُهَا . وَقَالَ ابْنُ عَبَّاسٍ { لَقَدْ كَانَ لَكُمْ فِي رَسُولِ اللَّهِ أُسْوَةٌ حَسَنَةٌ} .
Ibn Abbas (Allah be pleased with them) reported about (declaring of one's woman) unlawful as an oath which must be atoned, and Ibn 'Abbas said: Verily, there is in the Messenger of Allah (ﷺ) a model pattern for you.
Reference : Sahih Muslim 1473aIn-book reference : Book 18, Hadith 25USC-MSA web (English) reference : Book 9, Hadith 3494