Sahih Bukhari Volume 1, Book 8, Hadith 456

حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ يَحْيَى، عَنْ عَمْرَةَ، عَنْ عَائِشَةَ، قَالَتْ أَتَتْهَا بَرِيرَةُ تَسْأَلُهَا فِي كِتَابَتِهَا فَقَالَتْ إِنْ شِئْتِ أَعْطَيْتُ أَهْلَكِ وَيَكُونُ الْوَلاَءُ لِي‏.‏ وَقَالَ أَهْلُهَا إِنْ شِئْتِ أَعْطَيْتِهَا مَا بَقِيَ ـ وَقَالَ سُفْيَانُ مَرَّةً إِنْ شِئْتِ أَعْتَقْتِهَا وَيَكُونُ الْوَلاَءُ لَنَا ـ فَلَمَّا جَاءَ رَسُولُ اللَّهِ صلى الله عليه وسلم ذَكَّرَتْهُ ذَلِكَ فَقَالَ ‏"‏ ابْتَاعِيهَا فَأَعْتِقِيهَا، فَإِنَّ الْوَلاَءَ لِمَنْ أَعْتَقَ ‏"‏‏.‏ ثُمَّ قَامَ رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى الْمِنْبَرِ ـ وَقَالَ سُفْيَانُ مَرَّةً فَصَعِدَ رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى الْمِنْبَرِ ـ فَقَالَ ‏"‏ مَا بَالُ أَقْوَامٍ يَشْتَرِطُونَ شُرُوطًا لَيْسَتْ فِي كِتَابِ اللَّهِ، مَنِ اشْتَرَطَ شَرْطًا لَيْسَ فِي كِتَابِ اللَّهِ فَلَيْسَ لَهُ، وَإِنِ اشْتَرَطَ مِائَةَ مَرَّةٍ ‏"‏‏.‏ قَالَ عَلِيٌّ قَالَ يَحْيَى وَعَبْدُ الْوَهَّابِ عَنْ يَحْيَى عَنْ عَمْرَةَ‏.‏ وَقَالَ جَعْفَرُ بْنُ عَوْنٍ عَنْ يَحْيَى قَالَ سَمِعْتُ عَمْرَةَ قَالَتْ سَمِعْتُ عَائِشَةَ‏.‏ رَوَاهُ مَالِكٌ عَنْ يَحْيَى عَنْ عَمْرَةَ أَنَّ بَرِيرَةَ‏.‏ وَلَمْ يَذْكُرْ صَعِدَ الْمِنْبَرَ‏.‏

Narrated By 'Aisha : Barira came to seek my help regarding her manumission. I told herself you like I would pay your price to your masters but your Al-Wala(1) would be for me." Her masters said, "If you like, you can pay what remains (of the price of her manumission), (Sufyan the sub-narrator once said), or if you like you can manumit her, but her (inheritance) Al-Wala would be for us. "When Allah's Apostle came, I spoke to him about it. He said, "Buy her and manumit her. No doubt Al-Wala(1) is for the manumitted." Then Allah's Apostle stood on the pulpit (or Allah's Apostle ascended the pulpit as Sufyan once said), and said, "What about some people who impose conditions which are not present in Allah's Book (Laws)? Whoever imposes conditions which are not in Allah's Book (Laws), his conditions will be invalid even if he imposed them a hundred times."