Reference for Chullin 73:28

ומה מחיים קאי עלה בלאו ועשה לאחר מיתה מיבעיא

but whereas the animal is still alive [one who partakes of it transgresses] a positive law,<span class="x" onmousemove="('comment',' For the contravention of a prohibition implied by a positive law is regarded as an infringement of a positive commandment.');">¹⁴</span>

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