Reference for Chullin 47:11

ועשהו חטאת הא לאו הכי דרשינן ק"ו

Now this is so, only because it is written in the Divine Law, 'And it shall determine it for the sin-offering', but without this verse one would have applied the a fortiori argument!<span class="x" onmousemove="('comment',' Although the law in connection with the Day of Atonement is stated to be a statute. This being so, the a fortiori argument should be applied in our Mishnah, with the result that the Red Cow be also rendered valid by breaking its neck.');">⁷</span>

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