What is the ruling on uttering a divorce to threaten, with the intention of it taking effect for major matters, not minor ones, and what is the ruling on one who said to his wife, "You are divorced" one time?

The suspension of divorce depends on the husband's intention at the time of making the oath. If he intended to prevent his wife from going out at a specific time or to a distant place, the divorce does not occur unless what he intended is fulfilled. However, if he intended to absolutely prevent her from going out without his permission, then the divorce occurs every time she disobeys his command. If the oath was intended as a threat and a prohibition, the majority of scholars hold that divorce occurs, while Ibn Taymiyyah holds that it does not occur and an expiation for an oath suffices. A husband who has divorced his wife with a single divorce can take her back before the end of her waiting period by word or deed (with the intention of reconciliation), and a new contract or witnesses are not required for reconciliation.