He drank something after Fajr during a voluntary fast. Does he have to offer expiation?

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Fasting on Saturdays
He intended to fast ‘Ashoora’, then he did not fast it; how can he make up what he missed out on of reward and virtue?

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She has to offer expiation for killing but she cannot free a slave or fast, so can she feed a number of poor persons?
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Fasting on Saturdays
He intended to fast ‘Ashoora’, then he did not fast it; how can he make up what he missed out on of reward and virtue?

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