The Month of Shevat
The month of Shevat is the eleventh month counting from Nisan. As it states in the Book of Yirmeyahu (Jeremiah), 'On the twenty-fourth day of the eleventh month, the month of Shevat...' (Yirmeyahu 1). In the general calendar year of Jewish tradition, which begins with Tishrei, it is the fifth month.
"ROSH CHODESH" OF SHEVAT
The twelve-month sequence of months making up the Hebrew Calendar is as follows:
As can be seen from the bolding of the last three months of the year, the sequence of months preceding, including and following the Month of Shevat is Tevet, Shevat, Adar. Tevet is always an "incomplete" month, consisting of twenty nine days. Therefore, the Rosh Chodesh of Shevat, its "head," or "beginning," or, more accurately its "lead-in" is only one day, the first of Shevat. On the other hand, Shevat is a month that is always "full," consisting of thirty days. Therefore, the Rosh Chodesh of Adar, or its lead-in, consists of two days or, let me risk another metaphor, a "head" and a "tail." The first of these, the "tail" is the thirtieth of Shevat, completing that month; the second, the "head," is the first of Adar.
BIBLICAL HISTORY OF SHEVAT
On the first of the month, Moshe, inspired by prophecy from G-d, began to recite the words of the Book of Devarim to Israel. "On the other side of the Jordan, in the land of Moab, Moshe began explaining this law, saying..." (Devarim 1). He reviewed many of the Laws that had been taught at Sinai and at the "Ohel Moed," the "Tent of Meeting," the gathering place of the Jewish People around the Mishkan, where they had come to learn Torah from Moshe. The Book of Devarim is called "Mishne Torah," "Review of Torah," for this reason. He also taught them many additional laws at that time.
Moshe rebuked the People of Israel there for all their rebellions against Hashem during the forty-year period in the desert. He told them of the great reward they would receive if they faithfully observed the Torah, and the terrible punishments they would suffer if they did not. One might have thought that Moshe was exaggerating in his description of the punishments; however, contemplating the Holocaust, which occurred in our own century, one realizes that Moshe fell not one iota short in his description of the torments our People would suffer in bad times throughout our history.
He prepared them for their entry into, conquest and possession of the land of Israel which, thank G-d, has also re-occurred in our time. He concluded by blessing them, before his death, with some of the most inspiring language in all of the Bible.
For thirty-seven days, Moshe spoke these words to all Israel. He began the first of Shevat and ended the seventh of Adar. His first words were:
"You have dwelt long enough on this mountain. Turn and take your journey, and come to the Amorite mountain and all its neighbors, in the Aravah, on the mountain, and in the lowland, and in the south, and at the seacoast; the land of the Canaanite and the Lebanon, until the great river, the Euphrates River. See! I have given the Land before you; come and possess the Land that Hashem swore to your forefathers, to Avraham, to Yitzchak, and to Yaakov, to give them and their children after them."
His concluding words were:
"There is none like G-d, O Jeshurun; He rides across heaven to help you, and in His majesty through the upper heights. That is the abode of G-d immemorial, and below are the world's mighty ones; He drove the enemy away from before you, and he said, 'Destroy!' Thus Israel shall dwell secure, solitary, in the likeness of Yaakov, in a land of grain and wine; even his heavens shall drip with dew."
"Fortunate are you, O Israel: Who is like you! O People delivered by Hashem, the Shield of your help, Who is the Sword of your grandeur; your foes will try to deceive you, but you will trample their haughty ones." (Devarim 33).
The later Sages have, therefore, said that the first of Shevat is comparable to the day of the giving of the Torah. Just as the sixth of Sivan, on which the Torah was given to Israel, remains forever suitable for the renewed acceptance of the Torah, similarly is the heart of the Jew newly receptive to the Torah on the first of Shevat, because on that day they began to receive the Book of Devarim from Hashem, through Moshe.
Because the period of transmission of the Book of Devarim was this thirty-seven day interval, all the days from the first of Shevat until the seventh of Adar are especially well suited for renewed inspiration in the study of Torah and the doing of Mitzvot.