What is the ruling on one who swore by triple divorce concerning something that would not happen, but then it happened against his will?

The fatwa we adopt is that whoever breaks an oath sworn by divorce, his wife is irrevocably divorced with three talaqs. This is the opinion of most scholars. However, Sheikh al-Islam Ibn Taymiyyah holds that an oath sworn by divorce, which is not intended to effect a divorce but rather to threaten or emphasize a matter, has the same ruling as an oath sworn by Allah. If the oath is broken, the one who swore it must offer an expiation for an oath, and no divorce occurs. If divorce is intended, he holds that pronouncing three talaqs at once counts as one. Breaking an oath varies depending on what was sworn upon. If one swears concerning something that cannot occur, he has broken the oath merely by swearing it. If one swears concerning something possible, and is compelled to do it, some scholars have held that no breach of oath occurs in this case. The legitimate oath is swearing by Allah the Almighty. As for swearing by divorce, it is among the oaths of the dissolute.