The Book of Divorce (Kitab Al-Talaq)
Muslim :: Book 9 : Hadith 3606
Abu Huraira (Allah be pleased with him) reported Allah's Messenger (may peace be upon him) as saying: A son does not repay what he owes his father unless he buys him (the father) in case he is a slave and then emancipates him. In the narration transmitted by Ibn Abu Shaiba there is a slight change of words.