لِأَنَّهَا لَا تَسْتَقِرُّ مَعَ جَرَيَانِ الْمَاءِ
Meaning: Because impurity does not remain settled as the water flows.
Flow is a reason that contamination need not remain fixed at one point. Nevertheless, actual flowing water can still be affected by impurity.
Therefore, absence of a relevant effect remains a separate condition.
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Impurity in Stagnant and Running Water, Large Ponds, and Aquatic Creatures
لِأَنَّهَا لَا تَسْتَقِرُّ مَعَ جَرَيَانِ الْمَاءِ
Meaning: Because impurity does not remain settled as the water flows.
Flow is a reason that contamination need not remain fixed at one point. Nevertheless, actual flowing water can still be affected by impurity.
Therefore, absence of a relevant effect remains a separate condition.