"A man came to the Prophet of Allah and said: 'O Prophet of Allah,' and that he had declared Zihar to his wife, then he had intercourse with her before he did what he had to do. He said: 'What made you do that?' He said: 'O Prophet of Allah! I saw the whiteness of her calves in the moonlight.' The Prophet said: 'Keep away until you have done what you have to do.' (One of the narrators) Ishaq said in his Hadith: "Keep away from her until you have done what you have to do." The wording is that of Muhammad.  

أَتَى رَجُلٌ نَبِيَّ اللَّهِ ﷺ فَقَالَ يَا نَبِيَّ اللَّهِ إِنَّهُ ظَاهَرَ مِنِ امْرَأَتِهِ ثُمَّ غَشِيَهَا قَبْلَ أَنْ يَفْعَلَ مَا عَلَيْهِ قَالَ مَا حَمَلَكَ عَلَى ذَلِكَ قَالَ يَا نَبِيَّ اللَّهِ رَأَيْتُ بَيَاضَ سَاقَيْهَا فِي الْقَمَرِ قَالَ نَبِيُّ اللَّهِ ﷺ فَاعْتَزِلْ حَتَّى تَقْضِيَ مَا عَلَيْكَ وَقَالَ إِسْحَاقُ فِي حَدِيثِهِ فَاعْتَزِلْهَا حَتَّى تَقْضِيَ مَا عَلَيْكَ وَاللَّفْظُ لِمُحَمَّدٍ قَالَ أَبُو عَبْدِ الرَّحْمَنِ الْمُرْسَلُ أَوْلَى بِالصَّوَابِ مِنَ الْمُسْنَدِ وَاللَّهُ سُبْحَانَهُ وَتَعَالَى أَعْلَمُ  

A man made his wife like the back of his mother. He then had intercourse with her before he atoned for it. He came to the Prophet ﷺ and informed him of this matter. He asked (him): What moved you to the action you have committed? He replied: I saw the whiteness of her shins in moon light. He said: Keep away from her until you expiate for your deed.  

أَنَّ رَجُلاً ظَاهَرَ مِنَ امْرَأَتِهِ ثُمَّ وَاقَعَهَا قَبْلَ أَنْ يُكَفِّرَ فَأَتَى النَّبِيَّ ﷺ فَأَخْبَرَهُ فَقَالَ مَا حَمَلَكَ عَلَى مَا صَنَعْتَ قَالَ رَأَيْتُ بَيَاضَ سَاقَيْهَا فِي الْقَمَرِ قَالَ فَاعْتَزِلْهَا حَتَّى تُكَفِّرَ عَنْكَ