What is the ruling when a husband addresses his mother-in-law and says, 'Your daughter is divorced,' when he has a wife and another daughter belonging to the mother-in-law?

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The wife is divorced. The legal ruling is that the husband is not believed if he subsequently claims he intended the other daughter who is not his wife, as he lacks the legal capacity to divorce a woman other than his spouse. Ahmad stated regarding this scenario that the husband is condemned (must swear by the oath/is held accountable) and his claim is not accepted.