What is the ruling when a husband tells his two wives, 'You two are divorced for a thousand if you both will it,' and both affirm their will?

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When the husband states, 'You two are divorced for a thousand if you both will it,' and both wives respond, 'We have willed it,' the divorce occurs for both wives as a final, irrevocable separation (ba'in). The thousand dirhams become obligatory upon them jointly, apportioned according to the amount of their respective dowries (mahr). This ruling is supported by Ibn Hamid and the school of Ahl al-Ra'y, and is one of the opinions of Al-Shafi'i. The affirmation of will must be made verbally; any claim of intention solely in the heart, without verbal expression, is invalid and will not be accepted.