Reference for Menachot 12:13

ונילף מבמה

Has not R'Zera said in the name of Rab: If a non-priest slaughtered the Red Cow it is invalid; and Rab had explained the reason for it, namely, because the expressions 'Eleazar' and 'statute' are used in connection with it?<span class="x" onmousemove="('comment',' Cf. Num. XIX, 2, 3. Thus showing that the slaughtering must be performed by Eleazar i.e., by a priest and by none else, for the expression 'statute' indicates that that requirement is indispensable. Hence it is obvious that the slaughtering is considered a service of importance.');">¹³</span> - The case of the Red Cow is different, for it is in the category of things consecrated to the Temple treasury.<span class="x" onmousemove="('comment',' The reason why the slaughtering of the Red Cow must not be performed by a non-priest is not that the slaughtering is a service, for there are no 'services' in regard to things consecrated to the Temple treasury; but it is an express decree of the Torah that it shall be performed by a priest.');">¹⁴</span>

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