Reference for Bekhorot 33:6

רבן שמעון בן גמליאל אהעמיד קאי דנחית לדרי

Now, is this not an argument against R'Judah? - R'Judah can reply: Read: They and their offspring.<span class="x" onmousemove="('comment',' Which indicates two generations as being exempt.');">⁵</span>

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