Reference for Keritot 49:27

הא איתסרא לה מחיים

Now, if [it were forbidden] while still alive, then it has not yet atoned for the doubt!<span class="x" onmousemove="('comment',' I.e., if the second clause was to be interpreted that the heifer should be buried if the murderer was found after it had been brought to the 'rough valley' even though it was still alive, the argument for this ruling would be meaningless, since the ceremony of atonement, i.e., the breaking of the neck, had not yet taken place.');">¹⁵</span>

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