Does the husband's oath that his wife is divorced if his son returns to playing a specific game take effect, given that the husband intended internally to nullify his oath after a month? And what is the expiation for this oath if it does not take effect?

Most scholars are of the view that an oath of divorce conditioned on a contingency results in divorce upon the occurrence of the contingency, and that divorce pronounced with the triple utterance counts as three divorces.

Some scholars, such as Ibn Taymiyyah, are of the view that if an oath of divorce is not intended to effect a divorce but rather to threaten or emphasize, then its ruling is the same as an oath by Allah, and the one who swore it must pay an expiation for an oath, and no divorce takes place.

As for restricting an oath to a specific duration, if the one who swore it intended this at the beginning of the oath or during it, then the oath is restricted to the specified duration, and nothing occurs after its expiration, because oaths are based on the intention of the one who swore them, and intention specifies a general لفظ (utterance) and restricts an absolute one. However, an intention made after the completion of the oath's wording is not considered.