Reference for Arakhin 34:9

בתר חיובא דגברא אזלינן והא לא צריכא קרא למעוטי הוא למעוטי מאי

I might have assumed that since Rabbi said: We are guided by the liability of the person, we shall here too be guided by the liability of the person, therefore we are informed [that we are not so guided here].

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