What is the ruling of Islamic law regarding a husband who swore an oath of triple divorce that his mother would not wash anything belonging to him or his son, with the exception of his wife's clothes, and then the mother proceeded to wash them without her knowledge?

Anger that does not remove one's awareness does not affect the ruling on an oath. The majority of scholars hold that swearing an oath by divorce results in divorce upon breaking the oath, and that a triple divorce pronounced as such counts as three divorces. This is the prevailing opinion (al-mufta bihi). However, Sheikh al-Islam Ibn Taymiyyah held that the ruling on swearing an oath by divorce, when the intention is not to effect divorce but rather to threaten or emphasize, is the same as swearing by Allah: it necessitates an expiation for an oath (kaffarat yamin) and does not result in divorce. When divorce is intended, he held that a triple divorce pronounced as such counts as a single divorce. The prevailing opinion (al-mufta bihi) for us is that divorce occurs and that it counts as three. However, if the mother was not aware of the oath, the more preferred view for us is that it does not occur, if she is one who cares about her husband's oath. The differing opinions among scholars necessitate presenting the matter to trustworthy scholars.