Deuteronomy 20:19
The 15th of Sh'vat we celebrate the feast of Tu BiSh’vat, also known as Rosh Hashanah Leilanot or "New Year of the Trees". It’s the time of the year when we commemorate and honour the unique and sacred connexion between Judaism and nature.
This festivity is not prescribed in the Torah; it is first mentioned at the end of the Second Temple period as the crucial day for the tithes of trees’ fruits.
The fruits that ripened after the 15th of Shvat were included in next year recording. The Mishnah, on Rosh Hashanah treaty, tells us about the discussion between the school of Hillel and the School of Shamai concerning the date of Rosh Hashanah Leilanot.
The Mishnah alludes to Tu BiSh’vat as one of the four heads of the year; all of them establish the date of a New Year. "There are four beginnings of the year: the first of Nisan, the beginning of the year for kings and festivities; the first of Elul, the beginning of the year for the sabbatical year, and jubilee, for the sowing and vegetables. The first of Tishri and the School of Hillel tells us that the 15th of Shvat is the beginning of the trees’ year".
After the destruction of the Second Temple, the rules related to the tithes lost significance because they didn’t have any value beyond the Land of Israel. However, the festival persisted and, eventually, gained a slightly different meaning. Wherever there was a Jew, the feast helped them to preserve their connection to the Land of Israel. And although Tu BiSh’vat is a Holy Day closely related to Eretz Israel, it is commemorated also in the Diaspora since then.
In the 16th century, Isaac Luria and other cabalists, mystical sages of Tzfat (Safed) created a Seder for Tu BiSh’vat. The Seder is the symbolical way of representing God as the Tree of Life, with the branches spreading out to the earth full of life and blessings. The Tree of Life symbolizes the presence of God revealing to this world, the source of divine sustenance that constantly renews the entire creation.
Jewish Mystic teaches us that nature and human spiritual processes are all part of the same thing, of an incessant and tireless vital process, of an inexhaustible and indefinable energy, of Ein Sof (Unending), of God.
As part of this new interpretation of the festival, the mystic Seder reveals itself as an affirmation not only of the spiritual depth but also of the physical meaning of the natural world in our lives.