Shevat שבט

The Mishnah opens with a dispute: the school of Shammai sets the new year of the trees on the first of Shevat, the school of Hillel on the fifteenth. The law follows Hillel: Tu biShvat. By that day most of the Land of Israel's rain has fallen, and the tree begins its year anew—from this line are counted the years of orlah and the tithes of fruit. On the first of Shevat Moses began speaking the words of Deuteronomy—the last five weeks of his life.

The month names now in use are Babylonian: "the names of the months came up with us from Babylon", says the Jerusalem Talmud. In the Torah months are counted—"the first", "the seventh"—from Nisan, the month of the Exodus.