It was narrated from 'Aishah that she wanted to buy Barirah, but her masters stipulated that her Wala' should go to them. She mentioned that to the Prophet and he said:
Buy her and set her free, for Al-Wala' is to the one who sets the slave free. Some meat was brought and it was said: This is some of that which was given in charity to Barirah. He said: It is charity for her and a gift for us. And the Messenger of Allah gave her the choice, and her husband was a free man.