Narrated Hisham b. 'Urwah:

Khawlah was the wife of Aws ibn as-Samit; he was a man immensely given to sexual intercourse. When his desire for intercourse was intensified, he made his wife like his mother's back. So Allah, the Exalted, sent down Qur'anic verses relating to expiation for zihar.

حَدَّثَنَا مُوسَى بْنُ إِسْمَاعِيلَ، حَدَّثَنَا حَمَّادٌ، عَنْ هِشَامِ بْنِ عُرْوَةَ، أَنَّ جَمِيلَةَ، كَانَتْ تَحْتَ أَوْسِ بْنِ الصَّامِتِ وَكَانَ رَجُلاً بِهِ لَمَمٌ فَكَانَ إِذَا اشْتَدَّ لَمَمُهُ ظَاهَرَ مِنَ امْرَأَتِهِ فَأَنْزَلَ اللَّهُ تَعَالَى فِيهِ كَفَّارَةَ الظِّهَارِ ‏.‏