Does divorce take effect if the husband says to his wife: "You are divorced if you bring up this subject again," knowing that it is impossible for that subject not to be brought up at all?

Most scholars are of the view that if a husband makes his wife's divorce conditional on a certain condition, he cannot retract it. If the condition is met, the divorce occurs, regardless of whether the husband intended to effect the divorce or merely to threaten, emphasize, or prevent. Sheikh al-Islam Ibn Taymiyyah, however, is of the opinion that if the husband intended to effect the divorce upon the fulfillment of the condition, he can retract the conditional statement. If he did not intend to effect the divorce (but rather intended to threaten, emphasize, or prevent), then divorce does not occur; instead, he must offer an expiation for breaking an oath (kaffarat yamin).

Accordingly, the fatwa we adhere to is that if you brought up the subject your husband intended, divorce has occurred. As for the view of Sheikh al-Islam Ibn Taymiyyah, there are two scenarios for this issue: The first is that the husband intended to prevent and emphasize, and did not intend to make the divorce conditional. In this case, if you did it, divorce does not occur, but your husband must offer an expiation for breaking an oath. The second is that the husband intended to make the divorce conditional. In this case, he can retract this conditional statement, and if he does not retract it, divorce occurs if you do what was made conditional.