Is a wife considered divorced if her husband swore an oath of divorce saying, "My wife is unlawful to me if I return to sins," then he returned to sins forgetfully, knowing that he took her back and offered expiation?

The prohibition of a wife is a matter of disagreement among jurists. It is considered a major irrevocable divorce (baynunah kubra) by the Malikis, and a form of dhihar (injurious assimilation) by the Hanbalis. For the Shafi'is, it depends on the intention, and this is the most preponderant and authoritative opinion (al-qawl al-rajih al-mufta bihi). Therefore, if the intention of the one who spoke it was to divorce his wife in the event of his returning to sins, then she is divorced from him. He may take her back during her 'iddah (waiting period) if he did not intend three divorces. He must repent from his sins and refrain from swearing by this or any other لفظ (wording) that leads to separation and prohibition of the wife. Preventing oneself from sins should not be by frightening oneself with divorce, but by fearing Allah and being mindful of His constant watchfulness. If one returns to sins due to forgetting the condition (ta'liq), then nothing is incurred upon him, as the one who forgets is excused.