Reference for Bekhorot 6:44

אם פטרו את של ישראל במדבר דין הוא שיפטרו את של עצמן:

If so, why did the herd of R'Mari die?<span class="x" onmousemove="('comment',' Since his motives were good.');">²⁷</span> - Because he deprived them of their holiness.<span class="x" onmousemove="('comment',' By transferring a share of them to heathens.');">²⁸</span> But has not Rab Judah said: One is permitted to make a blemish in a firstling before it comes into the world?<span class="x" onmousemove="('comment',' As the sanctity of a firstling only begins after its birth.');">²⁹</span> - There, [in the latter case] he deprives the animal of the holiness of being sacrificed on the altar but he does not deprive it of the holiness [of belonging to] the Priests.<span class="x" onmousemove="('comment',' Like a firstling with a blemish whose shearing is forbidden and work with which is prohibited, still possessing a certain degree of holiness.');">³⁰</span> But in the former case, he even deprives it of the holiness [of belonging to] the Priests.<span class="x" onmousemove="('comment',' Although he actually observes all the prohibitions with reference to a blemished firstling, it is really rendered, owing to the share of the heathens, an unconsecrated animal.');">³¹</span> Or, if you prefer, I may say that R'Mari B'Rahel knew how to make a valid transfer to a heathen.<span class="x" onmousemove="('comment',' To accept money from a heathen which is the valid method whereby a selling transaction is concluded with a gentile.');">³²</span> But we are afraid that another man may see this and go and do [likewise], thinking that R'Mari did nothing significant<span class="x" onmousemove="('comment',' Lit., 'did a mere word'.');">³³</span> [when transferring to a heathen].<span class="x" onmousemove="('comment',' By means of words only the transference was effected and no money was paid i.e., he simply informed the heathen that he had given him possession.');">³⁴</span> And thus he will be lead to commit an offence. <big><b>MISHNAH: </b></big>PRIESTS AND LEVITES ARE EXEMPT<span class="x" onmousemove="('comment',' Presumably from the first-born of an ass.');">³⁵</span> A FORTIORI: IF THEY EXEMPTED THE FIRST-BORN BELONGING TO THE ISRAELITES IN THE WILDERNESS,<span class="x" onmousemove="('comment',' This at present understood as meaning that since the Levites themselves exempted the asses of the Israelites in the wilderness, how much more should they exempt their own asses.');">³⁶</span> IT FOLLOWS A FORTIORI THAT THEY SHOULD EXEMPT THEIR OWN.

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