The supposition is that the carcass is intact and its time of entry unknown. In Abu Hanifa’s reasoning, its apparent condition is used to estimate a nearer period, giving a one-day-and-night lookback for prayers made with wudu from that water.
The ruling concerns those who actually used the well for wudu, not anyone who used other clean water.
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Impurity in Wells and Rules of Drawing Water
The supposition is that the carcass is intact and its time of entry unknown. In Abu Hanifa’s reasoning, its apparent condition is used to estimate a nearer period, giving a one-day-and-night lookback for prayers made with wudu from that water.
The ruling concerns those who actually used the well for wudu, not anyone who used other clean water.