Pesachim 16: Liquid Pure
Impurity, now in the context of liquid. All of which, in the slaughtering part of the Beit HaMikdash, were pure. But is that because they couldn't be impure or for other reasons? Also, liquid as a perquisite to food items that can become impure becoming impure. Plus - supporting Rav's interpretation (trying to) that blood can be impure from a d'Orayta level.
The skinny
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