Reference for Bekhorot 111:23

א"ר אלעזר

R'Simeon B'Eliakim raised an objection against the opinion of R'Eleazar: [The law of] an animal bought, applies also to an animal too young for sacrifice!<span class="x" onmousemove="('comment',' If he bought it before the seventh day from its birth, it no longer enters the shed to be tithed, this certainly being the case if he bought it as a full-grown animal. We see then that its being too young for sacrifice prevents consecration from taking place, and still the law of an animal bought applies to it.');">¹²</span>

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