Shalom!
On Ber. 8a why are the various explanations of Hash-m's 4 amos shel halacha limited to when the Bais Hamikdash was destroyed: Mikra, Mishna, Talmud and Halacha, etc.??
These are Hash-m's "amos" all the time!
Also, about the inyan of living in the same town as one's rebbe. The chiluk is in the gemara to the extent to which a person is "kayif". But by definition, if a person has a rebbe in the true sense, then he is kayif whether or not he lives in the same town?! Even according to Rashi where it is davka an issue of tochacha, presumably a talmid of a rebbe, a talmid chacham, in the classical sense would accept tochacha no matter where. So, what else can the gemara mean here?
Thanks.
1) The Gemara states, "From the day that the Beis ha'Mikdash was destroyed, Ha'Kadosh Baruch Hu has only the four Amos of Halachah." This implies that before the Beis ha'Mikdash was destroyed, he also had the Beis ha'Mikdash, as well as the four Amos of Halachah.
The Gemara, in other words, is addressing a question that many of us might have: If the Beis ha'Mikdash was the worldly dwelling place of the Divine Presence in this world, as it were, then when the Beis ha'Mikdash was destroyed, where does the Divine Presence dwell? The Gemara answers that it dwells in the four Amos of anyone who learns Torah.
2) One's rebbi will not be able to see him doing wrong if he does not live nearby, and he will not be able to give him rebuke.
All the best,
Yisrael Shaw