Book of ʾīlāʾ
Book of ʾīlāʾ
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Book of ʾīlāʾ

It is forbidden, just like ẓihār.

An oath of ʾīlāʾ is valid from any husband who has the capacity to pronounce divorce, except one who is incapable of intercourse—whether due to an illness from which no recovery is expected, complete castration, or paralysis.

If a husband swears by Allah Almighty, or by one of His attributes, that he will never have intercourse with his wife, or1 that he will abstain for a period longer than four months, he thereby becomes a muʾlī.2 At the wife’s request, the judge grants him a four-month respite beginning from the moment of the oath; after that he must choose between expiating the oath and resuming marital relations, or pronouncing divorce.

If he refuses to do either, the judge divorces her on his behalf.