Sunan Abi Dawud, Hadith 2239

Narrated Abdullah ibn Abbas: A woman embraced Islam during the time of the Messenger of Allah; she then married. Her (former) husband then came to the Prophet and said: Messenger of Allah, I have already embraced Islam, and she had the knowledge about my Islam. The Messenger of Allah took her away from her latter husband and restored her to her former husband.

حَدَّثَنَا نَصْرُ بْنُ عَلِيٍّ، أَخْبَرَنِي أَبُو أَحْمَدَ، عَنْ إِسْرَائِيلَ، عَنْ سِمَاكٍ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ، قَالَ أَسْلَمَتِ امْرَأَةٌ عَلَى عَهْدِ رَسُولِ اللَّهِ صلى الله عليه وسلم فَتَزَوَّجَتْ فَجَاءَ زَوْجُهَا إِلَى النَّبِيِّ صلى الله عليه وسلم فَقَالَ يَا رَسُولَ اللَّهِ إِنِّي قَدْ كُنْتُ أَسْلَمْتُ وَعَلِمَتْ بِإِسْلاَمِي فَانْتَزَعَهَا رَسُولُ اللَّهِ صلى الله عليه وسلم مِنْ زَوْجِهَا الآخَرِ وَرَدَّهَا إِلَى زَوْجِهَا الأَوَّلِ ‏.‏

sunnah.com