The booze was flowing like the river Jordan when the headliner finally stepped on the stage inside Scruffy Murphy's Irish Pub in Sunnyvale. The joint was packed, and the star was ready to launch into his act -- the one all about sin.

Sin between men and women. Sin between friends. Sin between brothers and sisters -- all over this land. That's what the Guinness-guzzling, chardonnay-sipping sinners came to hear.

``In 25 years, I've lectured in many different places,'' said the Rev. Kevin P. Joyce, wearing a heavy crucifix on a chain hanging to his belly. ``But last month was the first time I ever gave a theological speech in a bar. It's difficult enough, but in a bar?''

And so, he launched into a hard and funny monologue on the seven deadly sins.

That's right -- gluttony, lust, greed, anger, envy, sloth and pride. The stuff still haunts us all, which is why Joyce was speaking at a gig called Theology on Tap, a monthly gathering for young Catholic adults to explore their faith and moral issues in a relaxed setting outside of church.

``The point is to bring God into the mainstream,'' said Ricardo Labiaga. ``If young people aren't going to church, we'll bring him to wherever they go. And our people go to bars.''

Labiaga and his wife, Kara, are members of Silicon Valley Young Adult Ministry. They tried offering theological discussions at St. Cyprian Church in Sunnyvale but were disappointed by small turnouts. Then Sandy Butler, another member, learned about Theology on Tap, which originated 24 years ago in Chicago and has spread to more than 50 dioceses nationwide.

Or as Butler put it: ``That's cool, theology in a bar.'' And there are no restrictions on the drinking. ``Having rules would only spoil the experience.''

About 20 million American Catholics are in their 20s and 30s, and they make up 40 percent of adult Catholics. Traditionally they formed the backbone of parishes but now participate in fewer church activities than a generation ago.

St. Cyprian, said Butler, has the highest concentration of young adult Catholics in Silicon Valley, but it's hard to get them to Sunday Mass and even harder to get them to participate.

Butler, who is of Irish heritage, approached Sean O'Keefe with the Theology on Tap idea. The Irish immigrant owner of Scruffy Murphy's on Murphy Street, and a lapsed Catholic, agreed to host sessions at 7 p.m. on Sunday evenings once a month. And then something strange happened -- he started attending Mass at St. Cyprian.

``I've been reconverted,'' O'Keefe said as he set up the microphone for Tap.

A former pastor of St. Maria Goretti Church in East San Jose, Joyce runs Spirit Site, an institute at Santa Clara University. Basically he's a 21st-century missionary who teaches people how to live healthier through faith, meditation and study.

``A priest should be out in the streets and in the bars,'' he said. ``Jesus spoke where people were eating and drinking all of the time, so much so that he was accused of being a glutton and a drunk, which of course he was not.''

Reading from notes and framed nicely by the bar's cathedral ceiling, Joyce performed a delightful verbal juggling act -- equal parts theology, therapy and humor.

He traced the seven sins to the writings of the Desert Elders, spiritual leaders in the early Christian monastic movement in Egypt and Palestine. He borrowed liberally from Jesus and St. Paul for answers to the sins, particularly anger.

``We must be aware of angry thoughts as they arise,'' he said. Quoting St. Paul he said, ``Don't let the sun set on your anger.''

Joyce explained how talking about anger leads us to ``observe our thoughts and redirect them to God, and we gain peace of mind.'' That calmness allows us to adopt the ``Jesus method'' of eventually blessing whoever angered us.

Cristina Candelori was taking notes at Scruffy's long wooden bar, where she started with a glass of merlot and switched to Fat Tire beer. She talked about her anger against the peer pressure at her daughter's suburban school forcing students to covet the most expensive of everything.

Of her first Theology on Tap Candelori said, ``I think I'm going to learn a lot coming here.''

Group discussions followed Joyce's speech. Michael Matteuchi and Monica Wieck sat at a lively table. A few were old Catholics who had recently found their way back to their faith. Some were regulars with concerns.

``I had always envied Protestants because they carried their faith in their hearts in a way I didn't see Catholics,'' Matteuchi said. He had stopped attending Mass until members of a young adults ministry invited him to Theology on Tap -- the next of which will be March 13.

Wieck said of her table, ``This offers them something meaningful in their lives that they can't get anywhere else.''

Joyce agreed.

``I like this age group,'' he said. ``They're in their 20s to 40s, and they're looking for something meaty in their faith.''

For more information see www.SpiritSite.org; e-mail for general information, info@spiritsite.org; Father Joyce, frkevin@spiritsite.org; mail to 807 Washington St., Santa Clara, CA 95050; or call (408) 227-1137.