What is the ruling regarding someone who swore an oath of divorce not to do something, then did it out of forgetfulness?

It is not permissible to swear by divorce, nor is it permissible to trifle with its pronouncements. The majority of scholars hold that if someone does what they conditioned the divorce upon, forgetfully, their divorce takes effect. However, the Shafi'is are of the view that it does not take effect with forgetfulness, based on the hadith: "Lifted from my nation are error, forgetfulness, and what they are coerced into." Accordingly, according to the Shafi'i view, the divorce does not take effect, but adhering to the view of the majority is more cautious.