Reference for Temurah 41:8

ויש להן פדיון ולתמורותיהן פדיון חוץ מן הבכור והמעשר

- The reason there [why R'Eleazar says that only the money can be used for a burnt-offering] is because he may come to make a substitution"&gt;.<span class="x" onmousemove="('comment',' If he could bring the young of an exchange of a guilt-offering itself as a burnt-offering, he might make a mistake and bring it as the guilt-offering in place of the real guilt-offering.');">⁷</span>

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