Reference for Menachot 158:9

ומי אית ליה לרבי שמעון (בן אלעזר) לב בית דין מתנה עליהן

Behold R'Idi B'Abin stated in the name of R'Amram who cited R'Isaac who cited R'Johanan, The daily offerings which are not required for the community<span class="x" onmousemove="('comment',' There were always six lambs which had been examined and found free from blemish in readiness for the daily offerings, for although only two were required daily six were made ready in case of an emergency. Consequently on the last day of every year, i.e., on the twenty-ninth day of Adar, there were always four lambs left which were not required for the community. They could not be used as offerings, for from the first of Nisan lambs from the new stock only would be used. V. supra 49b.');">¹⁰</span> are, according to R'Simeon, not redeemed unblemished;<span class="x" onmousemove="('comment',' But they must be allowed to pasture until they become blemished when they may be redeemed. The fact that R. Simeon must resort to this measure indicates clearly that he holds that the mental stipulation of the Beth din with regard to the lambs, namely those that are not required shall be non-holy, is of no effect.');">¹¹</span>

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