What is the ruling on someone who said to his father in a moment of anger: "By divorce, we will leave this house," but they did not leave the house? Does this oath take effect, and is there an expiation for it?

The majority of scholars hold that if someone swears an oath by divorce and then breaks that oath, the divorce takes effect, whether the intention was to enact the divorce or to threaten. The presence of the wife is not a condition. Some scholars, like Ibn Taymiyyah, are of the view that the divorce does not take effect; instead, an expiation for an oath (kaffarat yameen) is required. Our fatwa is that divorce takes effect upon breaking the oath. Breaking the oath occurs by not leaving the house within the specified time or by the death of the one who swore the oath. If the divorce takes effect and it is revocable (raj'i), the wife can be taken back before the expiry of her 'iddah (waiting period). The permissible oath is by Allah Almighty, whereas swearing by divorce is among the oaths of the dissolute.