The tradition of fasting has a place in many religious practices

IF you're reading this before the sun has set, Rabbi Yossi Marcus and his family won't have eaten food or had a sip of water today.

During daylight hours Sunday, they noshed on traditional foods -- kreplach, a triangular pastry filled with ground meat, as part of a feast.

But when the sun went down, Marcus, his wife, Esty, their two daughters and millions of Jews around the world went to Kol Nidre services, the beginning of the holiday Yom Kippur.

From sundown Sunday to sundown today, no food, no water passes their lips.

Yom Kippur is perhaps the most familiar fasting holiday to many Americans.

The rules for fasting on Yom Kippur are ancient, originating from the most ancient versions of the Torah, the books of Jewish law that Christians consider the first five books of the Old Testament.

However, fasting has traditionally had a part in many religious traditions, both Judeo-Christian and Eastern.

Members of the Church of Jesus Christ of Latter-Day Saints fast on the first Sunday of every month. Muslims fast from dawn to dusk during the 30 days of Ramadan. Fasting is part of many Buddhist traditions.

While each faith has its own reasons to encourage the limiting of food intake, the concept is common across many faiths.

Marcus, who leads North Peninsula Chabad, a Jewish educational organization that provides classes and outreach for those who do not belong to a regular temple, says the purpose of fasting is to focus on the spirit.

"On Yom Kippur we are trying to be like angels, so we don't eat or drink," he says. "We separate ourselves from the physical world."

To bolster the sense of that separation from the physical, traditional dress is white, and bathing and washing are prohibited.

Marcus says responses to fasting are individual.

"Some people feel miserable and not spiritual at all," he says. "Me personally, at the end of fasting for a long time, I wouldn't go so far as to say it's a different consciousness, but it puts you into a different mood, a transcendent kind of state. It's hard to describe."

Hunger comes and goes throughout the day but eventually goes away.

"There's a certain sense of calmness, a different sense of perspective," Marcus says.

Yom Kippur isn't the only Jewish fasting holiday, but it is the most widely celebrated one. The six others

commemorate tragedies for the ancient Jewish tribes, such as the destruction of the temple in Jerusalem 2,000 years ago.

Fasting and praying were often linked in Jewish scripture. For example, when Moses went up to Mount Sinai to receive the Ten Commandments, it is said he fasted for 40 days.

Perhaps because of its Jewish origins, Christianity also has a history of fasting. In the gospels of Matthew, Mark and Luke, Jesus goes out to the desert and fasts for 40 days before he accepts his destiny of being the Messiah.

Jay Pimentel, a member of the Church of Jesus Christ of Latter- Day Saints in Alameda, says his church's tradition of fasting comes from Matthew 17:21. Jesus' disciples try to heal a boy possessed by a demon but can't. Jesus heals the boy, and the disciples asked why he succeeded when they failed. Jesus replied, "This kind does not go out but by prayer and fasting."

Modern-day Mormons fast for a particular purpose. "Individual members are encouraged to fast and pray when they have a challenge or a big decision to make," Pimentel says.

Also, the first Sunday of each month is a fast day. That Sunday's service is unplanned. "Instead of prepared sermons, individual members are allowed to take the pulpit and bear witness," he says.

The tradition in Pimentel's family is to eat dinner Saturday evening and then dinner Sunday evening, 24 hours later, but he says the details of how church members fast is up to them. "We try not to be rules-oriented," he says. "We try to teach the principle."

Fasting is a tradition Pimentel grew up with. "I do feel like I summon spiritual faith and energy when focused on a particular problem," he says. "I have seen miracles take place that I ascribe to fasting."

Mormons are not the only Christian faith to fast. Catholics traditionally eat only one small meal on Ash Wednesday and Good Friday, and they are asked to abstain from eating meat Fridays during Lent.

From these same Judeo-Christian roots springs the tradition of fasting in Islam.

Along with faith in God and Muhammed, daily prayer, concern for the needy and pilgrimage to Mecca, fasting is one of the five pillars of Islam.

During the month of Ramadan, which begins Oct. 27, Muslims do not eat or drink between dawn and dusk. Smoking and sexual relations are also prohibited.

Being without food or water can be uncomfortable, says San Mateo resident Motie Omari, but the benefits outweigh the discomfort.

"It's learning how to discipline your soul," he says.

Muslim fasting comes from its shared roots with Judaism and Christianity. He says, "When it was revealed the fasting was ordained, God said, 'Fasting has been ordained for you in the same way that it has been ordained for those who came before you, followers of all the prophets: Jesus, David, Solomon, Moses.'"