Reference for Chullin 70:46

לשמעינן דם שחיטה וכ"ש דם מגפתו

Then the same should be the case with the blood of a slaughtered animal, for it is written: Thou shalt pour it out upon the earth as water?<span class="x" onmousemove="('comment',' Deut. XII, 16. This verse suggests that blood is accounted as water.');">¹⁷</span>

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