Reference for Chullin 59:39

אין חוששין שמא יטרפו זה על זה

There is not here a wide open cut! - R'Jeremiah answered: Our Mishnah deals with the case of two persons holding one knife.<span class="x" onmousemove="('comment',' They hold the knife in a slanting direction, one holding the handle and the other the head of the knife, and in this way one would be cutting the organs high up towards the head and the other lower down towards the body of the animal. There is, however, only one cut made.');">²⁴</span>

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