Rosh Chodesh which literally means "Head of the Month" is a monthly holiday that celebrates the arrival of the new moon, marking the start of a new month in the Jewish calendar.
The Jewish Calendar is a lunar calendar with twelve lunar months and 354 days per year. Each lunar month consists of 29 1/2 days. Since it is impossible to switch months in the middle of the day, certain Hebrew months have twenty-nine days whilst others have thirty days.
In order for the Jewish Festivals to be synchronized with the proper season, for example Passover (Pesach) which must fall in the spring (in Israel - the Northern Hemisphere), a leap year is added every few years. In a nineteen year cycle there will be seven leap years.
The Jewish leap year, however, is not like the leap year in the Gregorian calendar which is one day added on at the end of February every four years. A Jewish leap year adds on an entire month to close the gap between the 354 day lunar calendar and the 365 day solar calendar. Since the month of Adar (approximately February-March) is the last month of the Hebrew year, we add on an extra month at this time. We then have Adar I and Adar II which assures us that the holidays will be celebrated in the proper season. Originally, the date of Rosh Chodesh was confirmed on the testimony of witnesses observing the new moon, a procedure known as Kiddush Hachodesh (sanctification of the month). After the Sanhedrin (an assembly of either 23 or 71 elders or rabbi's, appointed to sit as a tribunal in every city in ancient Israel) declared Rosh Chodesh for either a full 30 day month or a 29 day month, news of it would then be communicated throughout Israel and the diaspora.
This system was dependent on the functioning of the Sanhedrin to declare the month, and to communicate this month to far-flung Jewish communities. In the 4th century CE, this became impossible and instead a fixed calendar of 29 and 30 day months was instituted by Hillel.
At the end of a 29 day month, Rosh Chodesh is celebrated for one day, on the first day of the new month. At the end of a 30 day month, Rosh Chodesh is celebrated for two days - the 30th day of the previous month, and the 1st day of the new month.
With the exception of the month of Heshvan, the eighth month of the year, every single month of the Jewish Calendar has some sort of special day or special observance. The importance of Rosh Chodesh is therefore obvious.
The names of the months are not Hebrew but Babylonian. The Bible refers to the Jewish holidays only by the order of the months and not by the Babylonian names which were assigned long after the canonization of the Torah. For example, the Torah gives the date of Yom Kippur as the tenth day of the seventh month, whilst the date of Pesach is the fifteenth day of the first month.
The month of Adar is one of the most joyful and spiritually distinctive months in the Jewish calendar. It is the twelfth month of the year when counting from Nissan, and the sixth month when counting from Tishrei. In a regular year Adar has 29 days, but in a Jewish leap year the calendar expands to include two Adars: Adar I (30 days) and Adar II (29 days). The primary celebrations associated with the month take place in Adar II, while Adar I carries a quieter echo of the same spiritual themes. The sages teach that “when Adar enters, joy increases,” reflecting the deep association of this time with hidden miracles, reversal of fortune, and the power of inner faith.
The central holiday of Adar is Purim, commemorating the salvation of the Jewish people from destruction in ancient Persia during the events recorded in Megillat Esther. The story is remarkable because divine intervention is never openly mentioned; instead, salvation unfolds through a chain of seemingly natural events that reveal a concealed providence. Purim is celebrated through the reading of the Megillah, giving gifts to friends, charity to the poor, and a festive meal filled with happiness and gratitude. In walled cities such as Jerusalem, the celebration is observed one day later as Shushan Purim. In leap years, Purim is observed in Adar II, emphasizing that the joy and redemption associated with Adar reach their fullest expression in that second month.
The zodiac sign (mazal) of Adar is Pisces, represented by two fish. Fish live beneath the surface of the water, hidden from sight, symbolizing the concealed miracles that define this month. Just as fish are protected by the water that surrounds them, Adar reflects a spiritual protection that may not be immediately visible but is deeply present. This symbolism connects directly to the Purim story, where divine guidance operates quietly behind the scenes. Fish also multiply abundantly, symbolizing blessing, continuity, and resilience.
The precious stone traditionally associated with Adar is the amethyst (in Hebrew, achlamah). This gemstone is linked to clarity, calmness, and inner strength. Its tranquil energy reflects the emotional transformation of the month: fear turns into joy, vulnerability into courage, and uncertainty into trust. The tribe associated with Adar is Naftali. In the Torah, Naftali is described as swift and expressive, qualities that mirror the dynamic reversal experienced in Purim and the ability to move quickly from distress to celebration. Naftali’s blessing also contains themes of freedom and beauty, reinforcing the month’s message that redemption can arise suddenly and unexpectedly.
According to mystical tradition, each Hebrew month corresponds to a letter of the Hebrew alphabet, a human limb, and a specific spiritual faculty. The letter of Adar is ק (kuf). The shape of this letter extends below the writing line, symbolizing descent into hidden places and the ability to find holiness even in concealment. This reflects the essence of Adar: discovering divine presence within ordinary reality. The limb associated with Adar is the spleen. In traditional Jewish thought, the spleen is linked to laughter and emotional transformation. This connection beautifully aligns with the dramatic shift from threat to joy that defines the Purim story and the overall spiritual tone of the month.
Adar therefore emerges as a time of hidden strength, emotional renewal, and deep joy. Its themes weave together concealment and revelation, vulnerability and protection, danger and deliverance. Through its holidays, symbols, and spiritual correspondences, the month teaches that even when circumstances appear uncertain, a deeper pattern of care and meaning is unfolding beneath the surface. It is a month that invites celebration not only of what is seen, but of the unseen forces that guide life toward redemption and happiness.