Muwatta Malik, Book 29, Hadith 1177 (In-Book)

Yahya related to me from Malik that he had heard that a man asked al-Qasim ibn Muhammad and Sulayman ibn Yasar about a man who pronounced dhihar from his wife before he had married her. They said, "If he marries her, he must not touch her until he has done the kaffara for pronouncing dhihar."

وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ رَجُلاً، سَأَلَ الْقَاسِمَ بْنَ مُحَمَّدٍ وَسُلَيْمَانَ بْنَ يَسَارٍ عَنْ رَجُلٍ تَظَاهَرَ مِنِ امْرَأَتِهِ قَبْلَ أَنْ يَنْكِحَهَا فَقَالاَ إِنْ نَكَحَهَا فَلاَ يَمَسَّهَا حَتَّى يُكَفِّرَ كَفَّارَةَ الْمُتَظَاهِرِ ‏.‏

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also referenced under: Book 29, Hadith 21 (USC-MSA)