Narrated 'Aisha:

A man divorced his wife thrice (by expressing his decision to divorce her thrice), then she married another man who also divorced her. The Prophet was asked if she could legally marry the first husband (or not). The Prophet replied, "No, she cannot marry the first husband unless the second husband consummates his marriage with her, just as the first husband had done."

حَدَّثَنِي مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا يَحْيَى، عَنْ عُبَيْدِ اللَّهِ، قَالَ حَدَّثَنِي الْقَاسِمُ بْنُ مُحَمَّدٍ، عَنْ عَائِشَةَ، أَنَّ رَجُلاً، طَلَّقَ امْرَأَتَهُ ثَلاَثًا، فَتَزَوَّجَتْ فَطَلَّقَ فَسُئِلَ النَّبِيُّ ﷺ أَتَحِلُّ لِلأَوَّلِ قَالَ " لاَ، حَتَّى يَذُوقَ عُسَيْلَتَهَا كَمَا ذَاقَ الأَوَّلُ ".