Rosh Hashana 14

Today our rabbis discuss the disagreement stated in our past Mishna between Beit Shammai and Beit Hillel.  They want to clarify the whether the first of Shevat or the fifteenth of Shevat is the New Year for trees and for tithing.  Both agree that tithes will be counted toward the New Year if they are taken after that date.  It is just the actual date that is in question.

Looking to Rabbi Akiva as an example, the rabbis argue about whether the halacha follows Beit Hillel or Beit Shammai.  Rabbi Akiva tithes etrogim after picking one from a tree.  We learn about the particulars of the etrog and the etrog tree.  

Again, I find it amazing that our rabbis choose to focus on these small points of difference.  In the larger picture, they are looking to understand a practice, tithing, that was done only when the Temple was standing.  A dormant tradition explored in exhausting detail.  Why?  Did our Sages truly believe that the Temple would be rebuilt and that we would need this instruction to properly perform many mitzvot?  Did they believe that if we missed one of these points, our rituals would be without merit?

It is painfully difficult for me to imagine a society without an understanding of multiple truths.  But we know that even within Jewish tradition, practices and even philosophies changed dramatically.  Jewish sects - beyond our rabbinical tradition - interpreted the Tanach, too.  Our Sages must have known of people (or perhaps even themselves) who changed their beliefs.  Jews were deciding whether or not to follow rabbinical tradition.  So how could the rabbis be so certain that these exact rituals were required for Moshiach to come?