It’s rare that Chanukah and Christmas fall on the same day. Blame it on the calendar. Or calendars.

Christmas is always Dec. 25 under the Georgian calendar, which was begun by Pope Gregory XIII in 1583 (Unless it’s the Orthodox Christian Christmas, observed a few weeks later.) Chanukah jumps around. Some years, it’s early. Some years, like 2024, it’s later.

Why?

DVJournal asked Rav Shai Cherry, the rabbi at Congregation Adath Israel in Elkins Park, to explain.

“Anthropology meets the calendar,” said Cherry. This year the first night of Chanukah begins on Dec. 25—Christmas. The last time it fell on Christmas was 2005. The next time is 2035, then 2054.

“The Jewish calendar is lunar, and the new moon marks the new month,” said Cherry.  “The issue with a lunar calendar, like the Islamic calendar, is that lunar months are roughly 29.5 days. That means over time, any given month will slowly migrate through the Gregorian calendar, which is solar.

“But the holidays on the Jewish calendar are usually connected to harvests, which don’t migrate. So, the rabbis worked out a system whereby a leap month is added to the calendar seven times in every nineteen-year cycle.

“In a leap year, with an extra month added in the spring, the fall and winter holidays seem relatively late.

“That’s why Channukah is ‘late’ this year and coincides with Christmas. Sometimes, with two consecutive non-leap years, Chanukah is ‘early,’ and we get Thanksgivukkah.” Chanukah fell on Thanksgiving in 2013.

“The seventh day of Chanukah always falls on the new moon since Chanukah, an eight-day holiday, begins on the 25th of the month.

“Here’s where anthropology comes in. The end of Chanukah, when we light the most candles, falls on the new moon closest to the winter solstice. What to do during the longest and darkest days of the year? Gather with family and friends and banish the darkness with light!”

Just as Christmas is celebrated with family, friends, and good food, along with brightly lit decorations, Chanukah likewise is shared with loved ones as Jewish people worldwide light the menorah.

But Christmas and Chanukah have different origins—Christmas marks the birth of Jesus Christ, the Christian savior, and Chanukah commemorates the Jewish Maccabees’ victory over a much larger Syrian-Greek army after the Jews rebelled against being forced to worship Greek gods in 166 BCE A miracle occurred when a small flask of oil needed to rededicate the Temple in Jerusalem lasted eight nights.

“I’m grateful, as a Christian pastor, that Chanukah and Christmas, in 2024 A.D., come together on the same day. Thankful that Jesus was born a Jew and died a Jew and that He provided for us salvation, hope, love and grace to all who will follow him, Yeshua HaMashiach,” said the Rev. Dr. William Devlin, volunteer CEO WidowsAndOrphans.info. “He loves us eternally as we celebrate Chanukah and Christmas.”

Jeffrey Lasday, senior chief of external affairs with the Jewish Federation of Greater Philadelphia said, “The holiday of Chanukah is a festival of light and hope celebrating the Jewish successful battle for religious freedom, the first recorded battle for religious freedom in history. The Syrian Greeks, rulers of the land of Israel in 164  BCE, had outlawed all Jewish religious practices in the land and had defiled the Jewish Temple in Jerusalem. A small band of Jewish guerrilla fighters were able to defeat the overwhelmingly superior Syrian Greek army, rededicate the Temple and enable the Jews to once again practice their religion in their homeland.

“This miracle of the few overcoming the mighty, of light overcoming darkness, of religious freedom triumphing over religious persecution, provides us with the spark, the hope that soon we will be able to bring our hostages home.

“One of the songs sung at Chanukah, ‘Maoz Tzur,’ includes the words: ‘Rock of Ages, let our song praise thy saving power. You, amidst the raging foes were our sheltering tower. Furious, they assailed us, but your armor veiled us. And thy word broke their sword when our own strength failed us.’

“The words remind us that the Jewish people have faced darkness before and, despite the odds, have triumphed,” said Lasday.

On Thursday, Dec. 26, the Jewish Federation will bring together the local community for its Center City Chanukah Celebration at Rittenhouse Square Park at 5 p.m.