مُسْنَدُ أَحْمَدَ
Musnad Ahmad 1943
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that Ibn "Abbas said: The Messenger of Allah (ﷺ) said with regard to the mukatab [a slave who has drawn up a contract of manumission with his master and is buying his freedom in instalments]: “A portion of the diyah of a free man should be paid, commensurate with how much he had paid towards his manumission, and a portion of the diyah of a slave should be paid, commensurate with the extent to which he was still a slave."
Musnad Ahmad 1944Sahih (Darussalam) []