Sahih Bukhari Volume 7, Book 68, Hadith 5267

حَدَّثَنَا مُحَمَّدٌ، حَدَّثَنَا أَبُو مُعَاوِيَةَ، حَدَّثَنَا هِشَامُ بْنُ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ، قَالَتْ طَلَّقَ رَجُلٌ امْرَأَتَهُ فَتَزَوَّجَتْ زَوْجًا غَيْرَهُ فَطَلَّقَهَا، وَكَانَتْ مَعَهُ مِثْلُ الْهُدْبَةِ فَلَمْ تَصِلْ مِنْهُ إِلَى شَىْءٍ تُرِيدُهُ، فَلَمْ يَلْبَثْ أَنْ طَلَّقَهَا فَأَتَتِ النَّبِيَّ صلى الله عليه وسلم فَقَالَتْ يَا رَسُولَ اللَّهِ إِنَّ زَوْجِي طَلَّقَنِي، وَإِنِّي تَزَوَّجْتُ زَوْجًا غَيْرَهُ فَدَخَلَ بِي، وَلَمْ يَكُنْ مَعَهُ إِلاَّ مِثْلُ الْهُدْبَةِ فَلَمْ يَقْرَبْنِي إِلاَّ هَنَةً وَاحِدَةً، لَمْ يَصِلْ مِنِّي إِلَى شَىْءٍ، فَأَحِلُّ لِزَوْجِي الأَوَّلِ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ لاَ تَحِلِّينَ لِزَوْجِكِ الأَوَّلِ حَتَّى يَذُوقَ الآخَرُ عُسَيْلَتَكِ، وَتَذُوقِي عُسَيْلَتَهُ ‏"

Narrated By 'Aisha : A man divorced his wife and she married another man who proved to be impotent and divorced her. She could not get her satisfaction from him, and after a while he divorced her. Then she came to the Prophet and said, "O Allah's Apostle! My first husband divorced me and then I married another man who entered upon me to consummate his marriage but he proved to be impotent and did not approach me except once during which he benefited nothing from me. Can I remarry my first husband in this case?" Allah's Apostle said, "It is unlawful to marry your first husband till the other husband consummates his marriage with you."