صحيح البخاري Sahih Bukhari كتاب الفرائض The Book of Al-Farad (The Laws of Inheritance)
بَابُ إِذَا أَسْلَمَ عَلَى يَدَيْهِ:

(22) Chapter. If someone is converted to Islam through somebody else.

2 hadith
Hadith 6757
حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ ، عَنْ مَالِكٍ ، عَنْ نَافِعٍ ، عَنْ ابْنِ عُمَرَ " أَنَّ عَائِشَةَ أُمَّ الْمُؤْمِنِينَ أَرَادَتْ أَنْ تَشْتَرِيَ جَارِيَةً تُعْتِقُهَا ، فَقَالَ أَهْلُهَا : نَبِيعُكِهَا عَلَى أَنَّ وَلَاءَهَا لَنَا ، فَذَكَرَتْ ذَلِكَ لِرَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ، فَقَالَ : لَا يَمْنَعُكِ ذَلِكِ ، فَإِنَّمَا الْوَلَاءُ لِمَنْ أَعْتَقَ " .
Narrated Ibn `Umar: That Aisha, the mother of the Believers, intended to buy a slave girl in order to manumit her. The slave girl's master said, "We are ready to sell her to you on the condition that her Wala should be for us." Aisha mentioned that to Allah's Apostle who said, "This (condition) should not prevent you from buying her, for the Wala is for the one who manumits (the slave)."
Hadith Reference Sahih Bukhari / The Book of Al-Farad (The Laws of Inheritance) / Hadith: 6757
Hadith Grading محدثین: أحاديث صحيح البخاريّ كلّها صحيحة
Hadith 6758
حَدَّثَنَا مُحَمَّدٌ ، أَخْبَرَنَا جَرِيرٌ ، عَنْ مَنْصُورٍ ، عَنْ إِبْرَاهِيمَ ، عَنْ الْأَسْوَدِ ، عَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا ، قَالَتْ : " اشْتَرَيْتُ بَرِيرَةَ ، فَاشْتَرَطَ أَهْلُهَا وَلَاءَهَا ، فَذَكَرَتْ ذَلِكَ لِلنَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ، فَقَالَ : أَعْتِقِيهَا فَإِنَّ الْوَلَاءَ لِمَنْ أَعْطَى الْوَرِقَ ، قَالَتْ : فَأَعْتَقْتُهَا ، قَالَتْ : فَدَعَاهَا رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ، فَخَيَّرَهَا مِنْ زَوْجِهَا ، فَقَالَتْ : لَوْ أَعْطَانِي كَذَا وَكَذَا مَا بِتُّ عِنْدَهُ ، فَاخْتَارَتْ نَفْسَهَا ، قَالَ : وَكَانَ زَوْجُهَا حُرًّا " .
Narrated Al-Aswad: Aisha said, "I bought Barira and her masters stipulated that the Wala would be for them." Aisha mentioned that to the Prophet and he said, "Manumit her, as the Wala is for the one who gives the silver (i.e. pays the price for freeing the slave)." Aisha added, "So I manumitted her. After that, the Prophet caller her (Barira) and gave her the choice to go back to her husband or not. She said, "If he gave me so much and so much (money) I would not stay with him." So she selected her ownself (i.e. refused to go back to her husband)."
Hadith Reference Sahih Bukhari / The Book of Al-Farad (The Laws of Inheritance) / Hadith: 6758
Hadith Grading محدثین: أحاديث صحيح البخاريّ كلّها صحيحة