Shmuel was chayav mitah for paskening before his Rebbe -yet we find in the gemara cases of talmidim who paskened DIFFERENTLY than their Rebbeim - is there only a problem of paskeinng befre ones Rebbe or can one do so when he is not around -and may one pasken AGAINST ones Rebbe i general if one honestly feels that he is wrong - is that not a problem -but it seems that this is the case as talmidim in the gemara are cholek on their Rebbeim ?
mendy, ny,usa
This is what we wrote on the topic in Eruvin 63a:
2) HALACHAH: "MOREH HALACHAH BI'FNEI RABO"
QUESTION: Rava states that if a person issues a Halachic ruling in front of his mentor (Moreh Halachah bi'Fnei Rabo), if his mentor is actually present, then the Talmid is Chayav Misah. If his mentor is not present, it is Asur, but one is not Chayav Misah. It seems from the Gemara that "Lo b'Fanav," not in front of his mentor, means that the Talmid is more than three Parsa'os (twelve Mil) away from his mentor, and yet it is still forbidden to be Moreh Halachah.
How can this be resolved with the Gemara on 62b that says that Rav Chisda ruled in Kafri in the days of Rav Huna, his mentor, and Rav Hamnuna ruled in Charta d'Argaz in the days of Rav Chisda, his mentor? If it is forbidden to be Moreh Halachah even when not in front of one's mentor, how was it permitted for them to do so?
ANSWERS:
(a) TOSFOS (DH Rav Chisda) answers that Rav Chisda was a Talmid Chaver of Rav Huna, and Rav Hamnuna was a Talmid Chaver of Rav Chisda, and that is why it was permitted for them to be Moreh Halachah when they were not in front of their mentors. In front of one's mentor, though, it is forbidden even for a Talmid Chaver to be Moreh Halachah.
(b) TOSFOS in Sanhedrin (5b, DH Ela Im Ken) answers that for any Talmid it is permitted to be Moreh Halachah she'Lo bi'Fnei Rabo when the Talmid is more than three Parsa'os away, but only on condition that he has permission from his mentor to do so. When the Gemara says that it is Asur even she'Lo b'Fanav, it refers to when the Talmid did not get explicit permission from his mentor.
(c) The RAMBAM (Hilchos Talmid Torah 4:3) answers that it is only Asur to pass Halachic rulings even not in the presence of one's mentor if one makes himself an established Posek . It is permitted, though, to rule on an Halachic query on occasion when not in the presence of his mentor.
(d) The RASHBA and RAN explain that when the Gemara says that "she'Lo b'Fanav" is Asur, it means when the Talmid is within three Parsa'os but not directly in front of his mentor. If one is more than three Parsa'os away, though, even for a lowly Talmid is permitted to make Halachic rulings. (See Chart to Eruvin 63a)