Some insist that the change of the millennium doesn't take place until the calendar rolls over to 2001. But no matter when they think the current era comes to a close, people on both sides of the overall philosophical divide are taking firm stands.
"Jews should butt out of the turn of the millennium," said Rabbi Arthur Hertzberg, a historian and visiting professor of the humanities at New York University. "It's not our calendar. We are not at the turn of our millennium."
Many in the Jewish community share Hertzberg's perspective.
Two prominent kosher restaurants in the New York area canceled planned Shabbat-oriented New Year's Eve parties. The prominent kosher supervision agencies that supervise them prohibited Mendy's in Manhattan, and strongly discouraged Noah's Ark, in Teaneck, N.J., from holding such celebrations.
Others, however, say that although the millennium isn't an intrinsically Jewish occasion, it still provides an opportunity -- much like Rosh Hashanah -- for Jews to reflect on our experiences and goals.
"This next millennium, replete with all its hype, gives us an opportunity to look out at the world and to try and make sense of what we see, to attempt to clarify what we want the future to hold," Rabbi Rachel Sabath, an associate at CLAL: The National Jewish Center for Learning and Leadership, wrote in a recent essay.
"Particularly in a time when the world seems upside down, it becomes even more essential to have an orientation, a sense of time, core values that transcend all interpretations, all religions, and all political parties," she wrote.
Still others say that no matter what our personal feelings about the change in the Christian-created calendar, it would be naive for Jews to ignore the turn of the millennium.
Jews should be prepared for possible technological problems, they say, and should be concerned about a potential backlash by right-wing Christians whose messianic aspirations remain unfulfilled when the calendar rolls over and Jesus has not returned to earth.
"Though apocalyptic expectations have always been proven wrong, wrong doesn't mean inconsequential," Richard Landes, director of the Center for Millennial Studies at Boston University, warned at a recent symposium on the millennium, which was sponsored by the Anti-Defamation League.
"The more wrong people are, the more passionate they are," he said.
Rabbi A. James Rudin, director of interfaith affairs for the American Jewish Committee, is also concerned.
"A lot of my fellow Jews take the turning of the millennium as a joke, but I don't," he said. "For some Christians, Dec. 31 is just a night for a great party. But a lot of other Christians take it very seriously."
"There's the wise, prudential jubilee approach of introspection and atonement for what we've done wrong, which is the Catholic approach," he said. "Then there's the prophecy crowd from among extreme evangelical Protestants who make apocalyptic claims for the second coming of Jesus."
Until recently, prominent conservative evangelical leaders -- including the Revs. James Dobson, Jerry Falwell and James Kennedy -- were predicting mass upheaval and warning their followers to prepare by stockpiling dried food, water and weapons in advance of an apocalyptic scenario recounted in the Christian Bible's Book of Revelation.
Christian broadcaster Dobson even gave each of his 1,300 employees an extra $500 to prepare for Y2K, according to a report in the Religion News Service.
Several who had predicted widespread social crisis have in recent weeks largely backed off such doomsday scenarios, wrote the news service, but other Christian fundamentalists and extreme-right hatemongers remain a threat, according to "Y2K Paranoia: Extremists Confront the Millennium," a report published recently by the Anti-Defamation League.
Inherent in Christian theology is the belief that Jesus will return to earth, ushering in the messianic era.
There are some, primarily right-wing evangelical Christians, who believe that the historical stage has now been set for that chapter to begin, since conditions prophesied in their Bible have been fulfilled: The State of Israel's creation in 1948; Jerusalem's reunification under Jewish control in 1967; and the ingathering to Israel of oppressed Jews, particularly from the former Soviet Union, since the 1980s.
When there are high expectations "and then nothing happens, there could be a backlash," Rudin said.
"If Jesus doesn't come back, who can they blame?" Rudin asked. "Historically, Jews have often been blamed for not cooperating in this Christian end of the world plan."
Others are more concerned about technology than theology.
They say that a failure of computer systems worldwide to recognize the change of the millennium could have disastrous consequences for individuals, communities and the environment.
Rabbi Arthur Waskow, director of the Shalom Center, which is a division of ALEPH: Alliance for Jewish Renewal, says that the whole problem stems from an over-reliance on computers, which he has dubbed "techno-idolatry."
His concerns range from the potential interruption of crucial supplies of oil, food and medicines to what he believes is the worst case scenario: "a chemical plant or nuclear plant going haywire, releasing massive amounts of poisonous chemicals. Most nuclear plants require electricity to shut down, so not being able to do so could make serious trouble," he said.
To prepare, he and his wife have stockpiled two weeks' worth of supplies for five people: bottled water, cans of tuna, vegetables and fruit, as well as flashlights and batteries, and a radio powered by turning a crank. They are keeping lots of books, especially a Bible, close by.
Waskow may be one of a small number of Jewish voices calling for other Jews to take such precautionary measures, but he's not alone.
"How scared do you want to get?" Rabbi Jeff Glickman, spiritual leader of Reform Temple Beth Hillel in South Windsor, Conn., asked referring to the several examples of potential disaster that he could cite.
Glickman, too, is preparing for Y2K by stocking up on non-perishable food and filling a lined trash can with fresh water for each member of his six-person family. He is also taking "a considerable amount of money" out of the bank to hold in cash, he said.
"Banks interact with thousands of other institutions every day. If any garbage comes in from any of them they may have to stop and verify every transaction. How long would that take?" he wondered.
What's more, "there could be a horrible run on things at the end of December, like food and stocks, whether or not the computer glitch happens."
Glickman and Waskow have both tried to use their pulpits -- Glickman at his synagogue and Waskow through seminars at the Jewish Renewal retreat center Elat Chayyim in New York -- to convince Jews that the real solution to millennial concerns is to work toward a greater sense of community by increasing personal contact between people rather than continuing to rely so heavily on technology.
Glickman tried to organize his congregants into "family groups" of several people who live in the same area, with the idea that they would look out for each other and develop closer relationships.
Both the rabbis, however, have gotten a weaker response than they had hoped.
When speaking about it from the pulpit, Glickman said, "I feel like I'm in a Dunkin' Donuts, with the amount of glaze on people's eyes."
Still, the two rabbis aren't the only ones hedging their millennial bets.
"I for one am not ready to give up the batteries and bottled water in my kitchen cabinet," said Pam Schafler, an ADL lay leader who introduced the millennium symposium there last month.
For his part, Landes said that even if the calendar changes over from 1999 to 2000 without incident, debate and fear will not end.
"I don't think it's intelligent to assume that this will all decrease next year,'' he said.