Reference for Pesachim 194:3

והא רועה לרבי שמעון לית ליה כלל שמואל נמי חדא קאמר כל שבחטאת מתה בפסח קרב שלמים

- Rather, Samuel holds as R'Simeon, who maintained: The five sin-offerings are left to die.<span class="x" onmousemove="('comment',' v. supra 97a. Those die in all cases, this holding good of iv whether it was refound before atonement was made with the second or after. Similarly, if two are set aside as a security for each other, the unsacrificed one must die.');">³</span> But surely R'Simeon does not hold at all that [any sin-offering] must be left to graze?<span class="x" onmousemove="('comment',' How then can Samuel say', whatever must be left to graze in the case of a sin-offering'?');">⁴</span>

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