Joking with one’s wife’s sister

Question

Zayd and ‘Amr, for example, are married to sisters, and the said Zayd jokes indecently with his wife’s sister and openly commits the preliminaries of intercourse (dawa‘i al-jima‘). For this reason ‘Amr has cut off his relations with Zayd. So is this act of Zayd permissible in the Shari‘a, and is ‘Amr’s cutting off relations with Zayd in this way also permissible, or not?

Answer

This conduct is contrary to the Shari‘a and impermissible. The wife’s sister must observe hijab; seclusion with her is haram. If Zayd did not desist from his behaviour even after being admonished, and ‘Amr, in order to protect himself from his fitna, cut off relations with him and in this way protected his wife, then he did very well; this is exactly what he should do.

Source: Fatawa Mahmudiyya

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