Sahih al-Bukhari, Book 34, Hadith 119 (In-Book) ⓘ

Narrated `Urwa: Aisha said, "Barira came to me and said, 'I have agreed with my masters to pay them nine Uqiyas (of gold) (in installments) one Uqiya per year; please help me.' I said, 'I am ready to pay the whole amount now provided your masters agree that your Wala' will be for me.' So, Barira went to her masters and told them about that offer but they refused to accept it. She returned, and at that time, Allah's Messenger was sitting (present). Barira said, 'I told them of the offer but they did not accept it and insisted on having the Wala'.' The Prophet heard that." `Aisha narrated the whole story to the Prophet. He said to her, "Buy her and stipulate that her Wala' would be yours as the Wala' is for the manumitter." `Aisha did so. Then Allah's Messenger stood up in front of the people, and after glorifying Allah he said, "Amma Ba`du (i.e. then after)! What about the people who impose conditions which are not in Allah's Book (Laws)? Any condition that is not in Allah's Book (Laws) is invalid even if they were one hundred conditions, for Allah's decisions are the right ones and His conditions are the strong ones (firmer) and the Wala' will be for the manumitter."

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ جَاءَتْنِي بَرِيرَةُ فَقَالَتْ كَاتَبْتُ أَهْلِي عَلَى تِسْعِ أَوَاقٍ فِي كُلِّ عَامٍ وَقِيَّةٌ، فَأَعِينِينِي‏.‏ فَقُلْتُ إِنْ أَحَبَّ أَهْلُكِ أَنْ أَعُدَّهَا لَهُمْ وَيَكُونَ وَلاَؤُكِ لِي فَعَلْتُ‏.‏ فَذَهَبَتْ بَرِيرَةُ إِلَى أَهْلِهَا، فَقَالَتْ لَهُمْ فَأَبَوْا عَلَيْهَا، فَجَاءَتْ مِنْ عِنْدِهِمْ وَرَسُولُ اللَّهِ صلى الله عليه وسلم جَالِسٌ، فَقَالَتْ إِنِّي قَدْ عَرَضْتُ ذَلِكَ عَلَيْهِمْ فَأَبَوْا، إِلاَّ أَنْ يَكُونَ الْوَلاَءُ لَهُمْ‏.‏ فَسَمِعَ النَّبِيُّ صلى الله عليه وسلم فَأَخْبَرَتْ عَائِشَةُ النَّبِيَّ صلى الله عليه وسلم فَقَالَ ‏"‏ خُذِيهَا وَاشْتَرِطِي لَهُمُ الْوَلاَءَ، فَإِنَّمَا الْوَلاَءُ لِمَنْ أَعْتَقَ ‏"‏‏.‏ فَفَعَلَتْ عَائِشَةُ ثُمَّ قَامَ رَسُولُ اللَّهِ صلى الله عليه وسلم فِي النَّاسِ، فَحَمِدَ اللَّهَ وَأَثْنَى عَلَيْهِ، ثُمَّ قَالَ ‏"‏ أَمَّا بَعْدُ مَا بَالُ رِجَالٍ يَشْتَرِطُونَ شُرُوطًا لَيْسَتْ فِي كِتَابِ اللَّهِ، مَا كَانَ مِنْ شَرْطٍ لَيْسَ فِي كِتَابِ اللَّهِ فَهُوَ بَاطِلٌ وَإِنْ كَانَ مِائَةَ شَرْطٍ، قَضَاءُ اللَّهِ أَحَقُّ، وَشَرْطُ اللَّهِ أَوْثَقُ، وَإِنَّمَا الْوَلاَءُ لِمَنْ أَعْتَقَ ‏"‏‏.‏