Sunan an-Nasa'i, Hadith 3449 ⓘ
It was narrated that 'Aishah said: "I bought Barirah and her masters stipulated that her Wala' should go to them. I mentioned that to the Prophet and he said: 'Set her free, and Al-Wala' is to the one who pays the silver.' So I set her free and the Messenger of Allah called her and gave her the choice concerning her husband. She said: 'Even if you gave me such and such, I would not stay with him,' so she chose herself and her husband was a free man."
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا جَرِيرٌ، عَنْ مَنْصُورٍ، عَنْ إِبْرَاهِيمَ، عَنِ الأَسْوَدِ، عَنْ عَائِشَةَ، قَالَتِ اشْتَرَيْتُ بَرِيرَةَ فَاشْتَرَطَ أَهْلُهَا وَلاَءَهَا فَذَكَرْتُ ذَلِكَ لِلنَّبِيِّ صلى الله عليه وسلم فَقَالَ " أَعْتِقِيهَا فَإِنَّمَا الْوَلاَءُ لِمَنْ أَعْطَى الْوَرِقَ " . قَالَتْ فَأَعْتَقْتُهَا فَدَعَاهَا رَسُولُ اللَّهِ صلى الله عليه وسلم فَخَيَّرَهَا مِنْ زَوْجِهَا قَالَتْ لَوْ أَعْطَانِي كَذَا وَكَذَا مَا أَقَمْتُ عِنْدَهُ . فَاخْتَارَتْ نَفْسَهَا وَكَانَ زَوْجُهَا حُرًّا .
also referenced under: Book 27, Hadith 61 (In-Book) & Volume 4, Book 27, Hadith 3479 (DarusSalam)