Is a declaration of Zihar (likening one's wife to one's mother) nullified by saying 'Insha'Allah' (if God wills)?
General Chapter
Al-Mughni
Book of Zihar
Primary text
When a husband states to his wife, 'You are upon me like the back of my mother, insha'Allah,' the declaration of Zihar is not established. This view is explicitly held by Ahmad. This ruling extends to other oaths, such as saying, 'What Allah has not made unlawful for me is unlawful upon me, insha'Allah,' where no consequence follows. Shafi'i, Abu Thawr, and the Ahl ar-Ra'y share this position, and no contrary opinion is known among others. This is because the declaration functions as an expiable oath, allowing for a valid exception (Istithna'), similar to swearing by Allah or declaring one's wealth unlawful. The basis for this is the Prophet's statement: 'Whoever swears an oath and then says, "Insha'Allah," there is no breaking of the oath upon him.' It is also reported that 'Whoever swears and makes an exception, he may act as he wishes or retract without breaking the oath.'
Supporting text
If the husband says, 'You are unlawful to me,' or 'By Allah, I will not speak to you, insha'Allah,' the exception reverts to both statements collectively, provided there is no intention to apply the exception to only one part. If the exception is phrased as 'You are unlawful to me when God wills,' or 'except what God wills,' or 'until God wills,' all such formulations serve as an exception that lifts the ruling of Zihar.