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كتاب البيوع
34  
Sales and Trade
(67)
Chapter: Dealing with women in selling and buying
(67)
باب الْبَيْعِ وَالشِّرَاءِ مَعَ النِّسَاءِ
Sahih al-Bukhari 2155

Narrated `Aisha:

Allah's Messenger (ﷺ) came to me and I told him about the slave-girl (Barirah) Allah's Messenger (ﷺ) said, "Buy and manumit her, for the Wala is for the one who manumits." In the evening the Prophet (ﷺ) got up and glorified Allah as He deserved and then said, "Why do some people impose conditions which are not present in Allah's Book (Laws)? Whoever imposes such a condition as is not in Allah's Laws, then that condition is invalid even if he imposes one hundred conditions, for Allah's conditions are more binding and reliable."

حَدَّثَنَا أَبُو الْيَمَانِ، أَخْبَرَنَا شُعَيْبٌ، عَنِ الزُّهْرِيِّ، قَالَ عُرْوَةُ بْنُ الزُّبَيْرِ قَالَتْ عَائِشَةُ ـ رضى الله عنها دَخَلَ عَلَىَّ رَسُولُ اللَّهِ صلى الله عليه وسلم فَذَكَرْتُ لَهُ، فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ اشْتَرِي وَأَعْتِقِي، فَإِنَّ الْوَلاَءَ لِمَنْ أَعْتَقَ ‏"‏‏.‏ ثُمَّ قَامَ النَّبِيُّ صلى الله عليه وسلم مِنَ الْعَشِيِّ، فَأَثْنَى عَلَى اللَّهِ بِمَا هُوَ أَهْلُهُ، ثُمَّ قَالَ ‏"‏ مَا بَالُ أُنَاسٍ يَشْتَرِطُونَ شُرُوطًا لَيْسَ فِي كِتَابِ اللَّهِ، مَنِ اشْتَرَطَ شَرْطًا لَيْسَ فِي كِتَابِ اللَّهِ فَهْوَ بَاطِلٌ، وَإِنِ اشْتَرَطَ مِائَةَ شَرْطٍ، شَرْطُ اللَّهِ أَحَقُّ وَأَوْثَقُ ‏"‏‏.‏
Reference : Sahih al-Bukhari 2155
In-book reference : Book 34, Hadith 106
USC-MSA web (English) reference : Vol. 3, Book 34, Hadith 364
  (deprecated numbering scheme)