When Aisha intended to buy Barira, she said to the Prophet, "Barira's masters stipulated that they will have the Wala." The Prophet (ﷺ) said (to Aisha), "Buy her, as the Wala is for the one who manumits."
Sahih al-Bukhari Book 85, Hadith 36
← Previous Hadith Aisha said, "I bought Barira and her masters stipulated that the Wala would be for them." Aisha mentioned that to the Prophet (ﷺ) and he said, "Manumit her, as the Wala is for the one who gives the silver (i.e. pays the price for freeing the slave)." Aisha added, "So I manumitted her. After that, the Prophet caller her (Barira) and gave her the choice to go back to her husband or not. She said, "If he gave me so much and so much (money) I would not stay with him." So she selected her ownself (i.e. refused to go back to her husband)."

Sahih al-Bukhari Book 85, Hadith 35 Next Hadith → Allah's Messenger (ﷺ) said, "The wala is for the one who gives the silver (pays the price) and does the favor (of manumission after paying the price).

Sahih al-Bukhari Book 85, Hadith 37