What is the religious ruling regarding a man who swore by triple divorce upon his wife that she should not go to a certain place without his knowledge, and then she went, with him regretting it and intending to offer expiation without informing her?

The majority of scholars hold that swearing an oath of divorce leads to divorce upon breaking the oath, and that pronouncing divorce three times results in a triple divorce. This is the prevailing fatwa. However, some scholars, such as Ibn Taymiyyah, are of the view that an oath of divorce not intended to effect divorce is treated like an oath sworn by Allah, requiring an expiation for a broken oath (kaffarat yameen) and not leading to divorce. He also held that pronouncing divorce three times counts as a single divorce. If the wife was aware of her husband's oath and left without his knowledge, then a triple divorce has occurred, making her irrevocably divorced (bainunah kubra). If the wife was unaware of the oath and performed the action sworn against, then there is a difference of opinion regarding the occurrence of divorce. It is best to present the matter to trustworthy scholars.