Al-Imām al-Bukhārī narrates: Muḥammad ibn Salām narrated to us; he said: al-Muḥāribī narrated to us; he said: Ṣāliḥ ibn Ḥayyān narrated to us. He said: ‘Āmir al-Sha’bī said:

Abū Burdah narrated to me from his father that the Messenger of Allāh ﷺ said: “Three types of people will receive a double reward: (1) A person from the People of the Book who believed in his prophet and then believed in me; (2) A slave who fulfills the rights of Allah and the rights of his master; (3) And a man who has a slave-woman: he teaches her good manners and teaches her well, then he frees her and marries her—for him there are two rewards.”

Then ‘Āmir said: “We have conveyed this ḥadīth to you without any payment, whereas for a ḥadīth even shorter than this one, people used to travel all the way to Madīnah.”