Rabbi Explains Two-Day Rosh Hashanah Tradition Through Lunar Observation
Rabbi Yoel Ben-Nun recounts a profound personal experience observing the new moon, which illuminated for him the reasoning behind the traditional observance of Rosh Hashanah over two days. He explains that the Hebrew calendar, a complex system combining lunar months and solar years, relies on celestial calculations for its fixed calendar, which can differ from the visually observed new moon.
Ben-Nun observed the new moon on the evening of the second day of Rosh Hashanah this past year, realizing it aligned with the visually apparent lunar cycle as understood by the Sages. This observation led him to appreciate the wisdom of the Sages in establishing two days for the holiday, particularly due to potential discrepancies between the calculated and observed new moon.
He further discusses the practice of not blowing the shofar on the first day of Rosh Hashanah if it falls on a Shabbat, a custom rooted in concerns about violating Shabbat laws by carrying the shofar. However, Ben-Nun argues that this concern has diminished with modern communal eruvs (religious boundary enclosures) that permit carrying items within them.
Citing the Rambam and Ritba, he suggests that the Sages' decision to refrain from blowing the shofar on Shabbat during Rosh Hashanah might have stemmed from uncertainty about the exact day of the new moon. He also touches upon the concept of "Zichron Teruah" (remembrance of the shofar blast) as a possible Torah basis for not blowing the shofar on Shabbat, but finds this explanation less convincing than the practical concern of Shabbat desecration.
Reflecting on the dispute between Rabban Gamliel and Rabbi Yehoshua regarding the calendar, Ben-Nun concludes that the established calendar, even if not perfectly aligned with the visually observed new moon, is binding, as exemplified by Rabbi Akiva's interpretation of a verse in Leviticus.
