Jewish Calendar

As the days get shorter and the nights darker, I miss adding my household’s festive Chanukah lights to the holiday lights around us. The nature of the Hebrew calendar means that this year, by the time we come to the longest nights of winter, the chanukiyot that blazed in our windows will have been long emptied and put away. I feel the darkness more without them. I am left to think about the nature of time and the lunar calendar by which we Jews mark our lives.

In the 21st century, we have a hundred ways to keep track of time: the second, minute, hour, day, year. We have carbon dating, atomic clocks and quartz oscillators. Tick, tick, tick. Every digital device I own displays the time for me. Whether I am making toast or talking on the phone, I can always see a linear procession — one, two, three, on and on, start to finish.

The Hebrew calendar is rooted in the observable, cyclical world — moon and sun, dry season and wet, sunrise and sunset. Wherever you are, when three stars are visible in the sky, Shabbat has ended. When you see the first sliver of moon beyond the thin clouds, it is Rosh Chodesh (literally, “head of the month”), signaling the beginning of a new month. Every Jewish holiday is attached in this way to the turning Earth.

In a sense, the first day of Chanukah this year fell where it always does — on the 25th of Kislev — but because of the roughly 11-day difference between 12 lunar months and one solar year, its date varied once again according to the widely used Gregorian calendar. And so our ritual of lighting Chanukah candles, pushing back the encroaching darkness, was observed with Thanksgiving dinner — and then over its leftovers.

The Festival of Lights wasn’t the only holiday to occur earlier than normal this year. Summer was barely done when we sweated through services during the Days of Awe. Butter melted on the dinner table under the sukkah. But rest assured, in 5774, (traditionally, the number of years since Creation), Pesach will still happen in springtime. Like so much that is Jewish, the calendar adjusts to change even as it retains its ancient roots.

While Muslims follow a purely lunar calendar, meaning that they do not make adjustments to keep it related to the seasons — which explains why the holiday of Ramadan began in November in 2000 and July in 2013 — the Torah sets times for festivals according to moon phase and harvests.

The solution: a lunisolar calendar that Jews brought home with them when the Babylonian exile ended in the sixth century B.C.E. It consists of six 29-day months and six 30-day months and runs in 19-year cycles, with an extra month added about every three years to make sure that the calendar stays in sync with the solar year. This leap month is, somewhat confusingly, called Adar I because it is added before the regular month of Adar.

It is important for a community to know when rituals are to be properly observed. In biblical times, it was the priest’s responsibility to keep track; later, it was the Sanhedrin’s. It wasn’t until the fourth century C.E., when persecution threatened the Jewish power structure, that Hillel II instituted a fixed calendar.

People who come to Southern California from the East Coast complain endlessly that they “miss the seasons.” Here, as in Israel, it’s true that the changes of season are subtle. I notice the cool nights when dew settles on the grass and the warm, dry ones when the leaves of my sycamore begin to curl and scatter. From my desk, I watch the angle of the sunlight shift, the length of days change and know it is winter, spring, summer again.

The sun goes down, a day begins to gestate in the darkness. The moon comes into view. Every night it changes. The Hebrew calendar connects us to the physical world in a way our digital devices do not. Marked with times of setting sun and changing moon, the calendar’s pages can help us remember to notice the waxing and the waning, turning and returning, the very definition of what is infinite — change without beginning or end.