What is the ruling on someone who swore by divorce, saying to his wife: "If you speak to the second woman again, my first wife is divorced," and then he spoke to her and proceeded to marry her? Is his first wife divorced or not? And is expiation for breaking an oath (kaffarat yameen) incumbent upon him?

Scholars have differed concerning the ruling on swearing by divorce and making it conditional. The majority of them hold that divorce occurs absolutely upon breaking the oath, and this is the fatwa we follow. So, if you speak to the woman whom you swore by divorce not to speak to, then your wife will be divorced from you. If the divorce is less than three pronouncements, you may take her back during her 'iddah (waiting period).

Some scholars, such as Ibn Taymiyyah, are of the opinion that if swearing by divorce is not intended to effect divorce but rather for emphasis or prohibition, then divorce does not occur. Instead, the one who swore is obliged to pay an expiation for breaking an oath if he breaks it.