Musannaf Ibn Abi Shayba 13:1392

Abu Bakr narrated to us, he said: Ibn Fudayl narrated to us, from ‘Ata’, from Abu ‘Abd al-Rahman, that he entered into a *kitabah* (manumission contract) with a slave, and he gave him a quarter [of the amount]. And he said: This is the statement of ‘Ali: "And give them from the wealth of Allah which He has given you."