Reference for Chullin 59:22

אמר רב יהודה אמר רב

But if you say that the term shechitah applies only to the last stage of the slaughtering, then as soon as the person commenced to slaughter it, it can no longer be intended to serve as<span class="x" onmousemove="('comment',' Lit., 'it has been rejected from',');">¹⁵</span>

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