What is required of one who is accustomed to swearing by Allah falsely, and is expiation (kaffarah) obligatory for that?

A Muslim should not swear excessively by Allah, as this indicates a lack of glorification of Allah and a boldness towards Him. Allah Almighty has indeed condemned those who swear excessively. Excessive swearing falls into two categories:

1. Swearing concerning a matter one is determined to do: Expiation (kaffarah) becomes obligatory if one breaks the oath. If the oaths are numerous regarding a single matter before breaking the oath, only one expiation is required. However, if the sworn-upon matters are different, only one expiation is required.

2. Swearing as mere utterance without intention: This is considered a 'laghw al-yamin' (unintended oath) and requires no expiation.

3. Swearing an oath concerning something one believes to be untrue (al-yamin al-ghamūs - the immersive oath): This oath immerses its taker in the Fire and cannot be expiated. Repentance is obligatory for it. Imam Shafi'i, however, mandated expiation along with repentance for this type of oath.