Is expiation required for a wife's repeated oaths by Allah concerning trivial matters, and is it advisable to admonish her given the recurrence of these actions?

A Muslim should not swear excessively, based on the Almighty's saying: "And do not make [your oath by] Allah an excuse against being righteous" (Quran 2:224), and the Prophet's (PBUH) saying: "Indeed, an oath leads either to breaking it or to regret."

Swearing about things whose veracity is unknown constitutes a "Ghamus oath," which is a major sin. It is called "Ghamus" because it immerses its taker in Hellfire or in sin. According to the majority of scholars, there is no expiation for it other than repentance and seeking forgiveness.

The wife must repent and refrain from swearing. The husband must advise her and compel her to offer expiation if she swears and then breaks her oath.