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The World's Two "Tu"s
by Rabbi Avi Billet
January 29, 2010/ 14 Shvat 5770
The first mishnah in Rosh Hashanah says there are four “Rosh Hashanahs” in the year for different calendar events. They occur on the first of Tishrei, the first of Elul, the first of Nissan, and there is a debate about the Rosh Hashanah for trees. Beit Shamai says it is on the first of Sh’vat, while Beit Hillel says it is on the fifteenth of Sh’vat.
The specific calendar event determines the age of fruits in order to put them into different categories of types of tithing or to determine at what point fruits can be used (is it the second, third, or fourth year of the fruit on the tree? …which would determine its status.)
When the Talmud discusses the Rosh Hashanah of trees, it emphasizes that the reason this “new year” takes place in the month of Sh’vat is because the rainy season peaks during this month (perhaps as evidenced by the flooding which took place in Israel last week), and the trees have stored up sufficient hydration to last until the next rainy season.
Though in general we rule like Beit Hillel, and therefore celebrate the new year of trees on the 15th of Sh’vat (aka Tu B’Shvat), it would seem, following the logic of the rest of the mishnah, that Beit Shammai makes more sense! All the other Rosh Hashanahs take place on the first of a month. Why should this one be any different? If the month of Sh’vat is indeed the time period of the height of the rainy season, the specific date of that height is certainly up for debate. Is it the first of the month, or the fifteenth?
We are left to try to understand the thinking and reasoning of Beit Hillel.
Perhaps we can look to the other “Tu B…” on the calendar, the 15th of Av – Tu B’Av – for an explanation.
There are many reasons for the celebration of the Tu B’Av holiday. One of them is the completion of the gathering of the “atzei ha’ma’arakha” — the wood used for offerings on the altar in the holy Temple. These gatherings ended at this time because the 15th of Av is considered the hottest summer day, after which the temperature begins to drop and moisture in wood no longer evaporates as it did before. Dead wood found after that date is not fit to be used for offerings.
Rabbi Moshe Feinstein uses this event as proof that the completion of any project to which one devotes much time and effort is cause for celebration (Iggerot Moshe, O”C 1:157).
Perhaps Beit Hillel used a similar logic in determining the celebration of the Rosh Hashana of trees. As the calendar date contains a natural event that completes a cycle of necessary tree growth, it is a time to mark the calendar and celebrate the trees’ new year.
Comparing the “fifteenth of the month” dates is not a novel idea, as we make similar comparisons from the start of Pesach to the start of Sukkot — both of which begin on the 15th of their respective months, and both of which are similarly six months apart from each other.
The Bnei Yissaschar points out that both the 15th of Sh’vat and Av take place 40 days before the Talmud’s proposed dates for the creation of the world, and the creation of mankind (Rabbi Yehoshua says Nissan, and Rabbi Eliezer says Tishrei). The Talmud (Sotah 2a) says 40 days before the conception of each human, a heavenly voice declares who the intended spouse of the person will be.
There is much talk in rabbinic literature over how humans are compared to trees. Following the parallel between natural phenomena of the world and the human condition, the 15th of Sh’vat and Av are significant as days in which the future is outlined, with the coming days and months set up to be ones of fruitful rest, relaxation and enjoyment of G-d’s gifts to the world.