What is the ruling on a husband's statement to his wife, made in a moment of anger: "You are divorced if you sleep on this bed"?

The majority of scholars hold that a conditional divorce takes effect upon the fulfillment of the condition, regardless of whether the intent was divorce itself, emphasis, or prevention. This is the authoritative opinion (al-mufta bihi). So, if you made your wife's divorce conditional upon sleeping on the bed, then if that occurs, the divorce takes effect. However, the determination of the intended condition refers back to your intention and purpose. If you intended prevention for a specific period, then your oath is restricted to that period. If you break your oath, you can reconcile with your wife before the expiration of her iddah (waiting period), provided she has not completed three divorces.