Sahih Bukhari, Chapter: Manumission of Slaves

I went to Aisha and said, "I was the slave of Utba bin Abu Lahab. "Utba died and his sons became my masters who sold me to Ibn Abu Amr who manumitted me. The sons of Utba stipulated that my Wala should be for them." Aisha said, "Barira came to me and she was given the writing of emancipation by her masters and she asked me to buy and manumit her. I agreed to it, but Barira told me that her masters would not sell her unless her Wala was for them." Aisha said, "I am not in need of that." When the Prophet (SAW) heard that, or he was told about it, he asked Aisha about it. Aisha mentioned what Barira had told her. The Prophet (SAW) said, "Buy and manumit her and let them stipulate whatever they like." So, Aisha bought and manumitted her and her masters stipulated that her Wala should be for them." The Prophet (SAW);, said, "The Wala will be for the liberator even if they stipulated a hundred conditions."