Reference for Temurah 49:9

ולדי קדשים ממעי אמן הן קדושים

The text therefore adds: 'No man shall sanctify it',<span class="x" onmousemove="('comment',' The text therefore will mean this: Howbeit the bekor i.e., the firstborn of a man, that which is born a firstling unto the Lord, he shall not sanctify it, implying that the firstborn may not sanctify a firstling for another dedication.');">⁷</span>

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