Ibn Majah

Benefits and Issues:
➊
The example of a prohibited (mahram) relative becoming an owner is as follows: two brothers were slaves, and one of them was set free. If he then purchases the other, the second brother will become free merely due to being purchased by his brother, because brothers are mahram relatives; therefore, one brother cannot become the owner of the other. The same ruling applies to mother and son, father and daughter, brother and sister, maternal uncle and niece, paternal aunt and nephew, and so on.

➋
Whether the owner and the owned are both men (such as father and son), or both women (for example: mother and daughter), or one is a man and the other a woman (such as maternal aunt and nephew, or maternal uncle and niece), in all these cases, the ruling remains the same.

➌
Whether ownership is acquired through purchase, gift (hiba), or inheritance, in every case, that slave or slave-girl will attain freedom.

➍
In Islamic law, every kind of encouragement has been given to free slaves, and numerous laws have been established to help abolish slavery. For example:
- To kidnap a free person and enslave him has been declared haram (forbidden) and a grave crime. See: ( )
- Multiple methods for freeing slaves have been legislated, such as: mudabbar, umm walad, and mukatab, etc.
- The ownership of a mahram has been made a cause for freedom.
- The children born to a free man from a slave-girl have been declared free by birth.
- For some sins, the expiation (kaffarah) has been made the freeing of a slave or slave-girl, such as in cases of accidental killing (qatl khata) and zihar, etc.