What is the ruling regarding a man saying to his wife, "Do such-and-such, and you are divorced," when he intends to threaten her and does not desire divorce, and what is the ruling on this according to the madhhab of Ibn Taymiyyah if he is not certain about his intention?

If a man says to his wife, "If you do such and such, then you are divorced," intending thereby a threat, then according to Al-Kamal Ibn Al-Humam in "Fath Al-Qadeer," the divorce takes effect if the wife performs the action upon which the divorce was conditioned. However, according to Ibn Taymiyyah, as long as the intention was to threaten and not to effect a divorce, then the divorce does not take effect when the wife performs the action. And if there is doubt about the intention, the divorce does not take effect according to Ibn Taymiyyah's school of thought, because the default is the continuation of the marriage.