Chapter on the Prescribed Punishment for Unlawful Sexual Intercourse

Shaykh al-Islam—may Allah sanctify his soul—was asked:

What punishment is due for someone who has unlawful intercourse with his sister?

He replied:

As for someone who has unlawful intercourse with his sister, knowing that it is forbidden, he must be put to death. The evidence for this is the report narrated by al-Barā’ ibn ‘Āzib:

“My maternal uncle, Abū Burdah, passed by me carrying a banner. I asked, ‘Where are you going, Uncle?’ He replied, ‘The Messenger of Allah, may Allah bless him and grant him peace, has sent me to a man who married his father’s wife. He ordered me to strike off his head and take a fifth of his property.’”

And Allah knows best.

He—may Allah have mercy on him—was also asked:

A woman with a worthy husband and children became attached to a man from the outlying districts and lived with him in adultery. When her conduct became known, she sought to separate from her husband. Does she still have any rights over her children after this deed? Do they incur sin by severing ties with her? Is it permissible for someone who has ascertained that she did this to kill her in secret? If someone else does so, does he incur sin?