The Gemara says that Rebbe in our sugya holds we go by how the pasuk is written.the gemara asks that how could that be if we know that he normally holds that we go after the way the pasuk is read.The gemara answers that being that we have a gezera shava that implies the pasuk refers to the tree we must say that rebbe will agree in this case we go by how pasuk is wriiten.QUESTION-Why can't the gemara simply explain that really rebbe holds in our sugya as well that we go by how pasuk is read and the argument between Rebbe and Rabbanan is that Rebbe holds that 'Min Ha'etz' refers to the iron coming off the 'Tree' meaning that upon the iron hitting the wood of the tree the iron flew off.However Rabbanan hold that Min Hae'etz refers to the wood of the axe.After all Rabbenu chananel explains the second case of our Mishna to be reffering the iron flying off upon contact with the tree.
Aaron Massry, brooklyn ny
Reading the way it is read means a direct action causes a Chiyuv Galus, as is the opinion of the Rabbanan who hold, as you stated, that Min ha'Eitz means that the ax head happens to come off of the wood that is its handle (Ritva). Rebbe holds that the direct action of swinging the ax and the iron ax head flying off and killing someone is not Chayav Galus, but rather Karov l'Meizid (Rabeinu Chananel). Accordingly, there is no way he can derive the Passuk the way it is read. He would have ignored this Sevara and agreed with the Rabbanan, since his regular opinion is to read the Passuk as it is read, were it not for the Gezeirah Shaveh teaching that the Passuk is clearly discussing a secondary action of the tree splintering (which even Rabeinu Chananel says is also the case).
All the best,
Yaakov Montrose