It's the month of Adar, and in Jewish tradition, the beginning of Adar always means an "increase in joy." After all, the festive holiday of Purim, on Adar 15, is just two weeks away—or would be in a normal year. But though Adar started on February 4, Haman must have seen his shadow, for there are not two but six weeks to go until Purim.
The reason is simple—there's a leap month this year. As to why there is an extra month, that's a bit more complicated.
Everywhere in the world, months are the unit of time based on the cycles of the moon. But if you create a year out of twelve lunar months, as do the Jews and the Muslims, you will fall about eleven days short of a full solar year as measured (say) from one vernal equinox to the next. That is why, for Muslims, the fasting month of Ramadan slides around the year from summer to spring to winter and eventually back around again.
The reason this does not happen in the Jewish year is that the Jewish holidays are not only historical but also agricultural. Passover must occur "at its set time from year to year" (Exodus 13:10)—that is, in the spring—and Sukkot can take place only in the fall, "when you have gathered in the yield of your land" (Leviticus 23:39). How to achieve the requisite regularity? Give thanks to what is known as the Metonic cycle: i.e., the fact that nineteen solar years are almost precisely seven months longer than nineteen lunar years. By adding an extra month to seven out of your nineteen lunar years, you will be close enough to the solar year during most of the cycle and right on target at the end of it.
That is exactly what the Jewish calendar does. According to an algorithm that began to be developed as early as the 4th century C.E., leap months are to be added to the third, sixth, eighth, eleventh, fourteenth, seventeenth, and nineteenth years of each cycle. This year, 5771, happens to be one of them.
It sounds complicated, but even our 365-day calendar falls a bit short of a solar year, which is why it must be adjusted by adding an extra day once every four years. In our clever "Gregorian" system, we add the extra day every time the year is divisible by four, unless it is also divisible by 100. So century years do not get the leap day unless (like 2000) they are also divisible by 400. If my figuring is correct, that amounts to a total of 97 extra days every 400 years. By comparison, the Jewish system of seven extra months in every nineteen years seems simple.
One rarely noticed peculiarity of the Jewish system is that—unlike with February 29, the extra day tacked on at the end of the second month of the secular year—the leap month comes before the "regular" month. A Jewish leap year has Adar 1 and Adar 2, and the "extra month" is Adar 1, not Adar 2. How do I know? For one thing, if you are marking the anniversary of a death that took place in Adar of a non-leap year, you do so during the second Adar, not the first. Of more general importance is that Purim, too, is delayed till Adar 2, so that Passover can fall in its normal place a month later. (There is a "Little Purim" on the appropriate date in Adar 1, but don't expect to see any little Esthers and Mordecais running around, or to be receiving any gifts of hamentaschen.)
All this systematization is a good thing, since disagreements about the calendar are not unknown in Jewish history, and they are not inconsequential. Some think the solar calendar was the original religious calendar of the Jews, replaced, after the return from exile in Babylonia, by the calendar used there. (Everyone agrees that the current names for the months are Babylonian.) It's certain that by late Second Temple times, a dispute over the calendar split the Jewish people into sects.
We know about this from two books of the Pseudepigrapha, works from the last couple of centuries before the Common Era that sound biblical but did not actually find their way into the canon. In two of these, 1 Enoch and Jubilees, we find detailed descriptions of a 52-week, 364-day year that falls precisely into four quarters, closely mimicking the solar year. The advantage of such a calendar is that the festivals fall on exactly the same day of the week every year. The disadvantage (besides the need to adjust slightly for the day-and-a-quarter annual discrepancy that still remains) is that other Jews were declaring months according to the moon and celebrating the festivals on different days.
A work found among the Dead Sea Scrolls interprets a verse from the book of the prophet Habakkuk ("Woe betide the man who makes his companions drink the outpouring of God's wrath . . .") as follows:
[T]he Wicked Priest . . . pursued the Teacher of Righteousness to consume him with the heat of his anger in the place of his banishment. In festival time, during the rest of the Day of Atonement, he appeared to them, to consume them and make them fall on the day of fasting, the sabbath of their rest.
It seems that this Wicked Priest, who is thought to have been the official High Priest in Jerusalem, tried to make the leader of the Qumran sect violate the day that the latter thought was Yom Kippur. As in a later imbroglio recorded in the Mishnah, this would have meant acknowledging that one man's calendar was right and the other's was wrong. Even had there been no pre-existing power struggle between these two Jewish groups, observing the festivals on different days would have pushed them apart in any case.
There are calendar distinctions among Jews today as well. Certain "deviants" from the standard calendar—that is, the calendar given out by synagogues and funeral homes—celebrate only one day for festivals instead of two. If, according to one calendar but not the other, the festival includes a Sabbath, the two groups will even find themselves reading different Torah portions on the same day.
Fortunately, today's difference does not pose the same risk of a fractious split in the Jewish people as did the lunar-solar dispute of Second Temple times. The "deviants" in today's case are the Jews who live in the land of Israel and follow the biblical schedule of festivals as they have always done, plus some Diaspora communities that have adopted the same system. After a few weeks, the two calendars always jiggle themselves back into place and the Jews of the world all find themselves back on the same page.
It's Adar, and sooner or later Purim will arrive. Let the joy increase.
Michael Carasik is the creator of The Commentators' Bible. He teaches at the University of Pennsylvania and the Reconstructionist Rabbinical College.
You can find this online at: http://www.jidaily.com/calendars