Does a divorce that you swore to falsely to your wife under duress take effect, or is it a Ghamus oath for which you must offer expiation?

What you undertook by swearing an oath of divorce is a heinous sin. Hasten to repent to Allah, increase your seeking of forgiveness, and do not repeat such an act. As for the divorce, it is effective according to the majority of scholars, and you may take your wife back before the completion of her iddah (waiting period) if this divorce does not complete the three divorces. Shaykh al-Islam Ibn Taymiyyah said: You are not bound by divorce nor by an expiation for an oath.