What is the ruling on expiation (kaffara), and is it permissible to feed instead of fasting despite being able to fast, but fasting would lead to divorce because the wife cannot endure the long period, knowing that he uttered al-Zihar while ignorant of its meaning, and then repented?

Scholars differ on the ruling concerning a wife becoming unlawful through the aforementioned wording. The preponderant opinion is that it depends on the husband's intention, so whatever he intended—whether ẓihār, divorce, or an oath—takes effect. If the intention was neither divorce nor ẓihār, then an expiation for an oath (kaffārat yamīn) is due. It is advisable to avoid resolving marital disputes with words that the husband might regret, such as divorce and ẓihār.