What constitutes a state of necessity that permits the consumption of prohibited items?

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The necessity that permits consumption is that where one fears perishing if they refrain from eating. This fear is not confined to starvation alone. Imam Ahmad stated that if a person fears for themselves, whether from hunger, or from the inability to walk and being left behind by a travelling group leading to ruin, or being unable to ride and thus perishing, the necessity applies, and this state is not limited to a specific duration.