Barirah came to Ayesha seeking her help with her writ of emancipation, as she had not yet paid any of it. Ayesha said to her, "Go back to your masters. If they agree that I pay off your contract on the condition that your right of guardianship goes to me, I will do so."Barirah mentioned this to her masters, but they refused, saying, "If she wishes to do this for you as a charitable deed, let her do so, but your right of guardianship will remain with us."Ayesha mentioned this to the Messenger of Allah ﷺ, and the Messenger of Allah ﷺ said to her, "Buy her and free her, for the right of guardianship belongs only to the one who frees the slave."Then the Messenger of Allah ﷺ stood up and said, "What is the matter with people who stipulate conditions not found in the Book of Allah? Whoever stipulates a condition not found in the Book of Allah, it is invalid, even if he stipulates it a hundred times. The condition of Allah is more deserving and more binding."
حدثنا عبد الله بن مسلمة وقتيبة بن سعيد قالا حدثنا الليث عن ابن شهاب عن عروة أن
أن بريرة جاءت عائشة تستعينها في كتابتها ولم تكن قضت من كتابتها شيئا فقالت لها عائشة ارجعي إلى أهلك فإن أحبوا أن أقضي عنك كتابتك ويكون ولاؤك لي فعلت فذكرت ذلك بريرة لأهلها فأبوا وقالوا إن شاءت أن تحتسب عليك فلتفعل ويكون لنا ولاؤك فذكرت ذلك لرسول الله ﷺ فقال لها رسول الله ﷺ ابتاعي فأعتقي فإنما الولاء لمن أعتق ثم قام رسول الله ﷺ فقال ما بال أناس يشترطون شروطا ليست في كتاب الله من اشترط شرطا ليس في كتاب الله فليس له وإن شرطه مائة مرة شرط الله أحق وأوثق
Bukhari narrated it, in the Book of the Contract of Manumission (Mukatab), the chapter on what is permissible regarding the conditions of the mukatab, etc., no. 2561 and no. 2717, and Muslim, in the Book of Emancipation, the chapter explaining that the right of inheritance (walaa) belongs to the one who freed the slave, no. 6/1504, from Qutayba, with this same chain.