أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّ عَائِشَةَ، أَرَادَتْ أَنْ تَشْتَرِيَ، جَارِيَةً تَعْتِقُهَا فَقَالَ أَهْلُهَا نَبِيعُكِهَا عَلَى أَنَّ الْوَلاَءَ لَنَا ‏.‏ فَذَكَرَتْ ذَلِكَ لِرَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ ‏"‏ لاَ يَمْنَعُكِ ذَلِكَ فَإِنَّ الْوَلاَءَ لِمَنْ أَعْتَقَ ‏"‏ ‏.‏

It was narrated from'Abdullah bin 'Umar that 'Aishah wanted to but a slave woman to set her free, but her people said: "We will sell her to you on condition that her loyalty (Walla) is to us," She mentioned that top the Messenger of Allah and he said: "That should not stop you. Loyalty belongs to the one who sets the slave free." Translation Not Available

Book Ref: Sunan An Nisai Book 44 Hadith 4644
Web Ref:  Sunan An Nisai Vol 5 Book 44 Hadith 4648