Does divorce take effect and is an oath atonement (kaffarat yamin) or divorce required for the husband who said to his wife: "Divorce and oath upon me (Ali al-Talaq wal Yamin), you will not sit with my mother again and you will not eat with her," then they reconciled, sat, and ate together?

The majority of scholars hold that swearing by divorce results in divorce upon breaking the oath, regardless of whether the intent was actual divorce or merely a threat, or anything else. This is the predominant fatwa. However, Sheikh al-Islam Ibn Taymiyyah is of the opinion that swearing by divorce, when the intent is not actual divorce but rather a threat or emphasis, takes the ruling of an oath by Allah. In this case, the one who swore must pay an expiation for an oath, and no divorce occurs. The phrase "divorce upon me and an oath" is an oath by divorce and an oath by Allah. Therefore, by the wife sitting and eating with the husband's mother, a divorce occurs, and an expiation for an oath becomes binding. The wife can be taken back if three divorces have not been completed and before the expiry of her iddah (waiting period). It is advisable to refrain from swearing by divorce in the future, as it is among the oaths of the dissolute. The lawful oath is swearing by Allah the Almighty.