Sunan Abi Dawud 3966
سنن أبي داود#3966SahihAmr ibn Abasah, said that Marrah ibn Ka'b said:I heard the Messenger of Allah (ﷺ) say: If anyone emancipates a Muslim slave, that will be his ransom from Jahannam
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiHasan
In-book reference: 31:41