Reference for Chullin 166:16

ליתיב וליבטליה קמוסיף אבנין וכתיב

And if he does not decide to leave it there, then it is an interposition!<span class="x" onmousemove="('comment',' Interposing between the blood of the bird sacrifice and the altar, and this would disqualify the service.');">⁹</span>

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