With assimilation soaring in the United States, particularly in Northern California, Israeli theologian Rabbi David Hartman is fascinated by the motivation that brings Jews into the synagogue during the High Holy Days.

Does Hartman believe sold-out services and standing-room-only crowds at High Holy Day services mean Jews are getting religion? No.

Does he believe there's hope for a more meaningful celebration of the High Holy Days in these times? Yes.

"Our ability to breathe new life into the Rosh Hashanah-Yom Kippur holidays will depend on how the Jewish people will once again rehabilitate their God-consciousness," said Hartman last week during a talk at the S.F.-based Jewish Community Federation.

The Brooklyn-born scholar and Orthodox rabbi, who made aliyah to Israel in 1971, founded Jerusalem's Shalom Hartman Institute in 1976, dedicated to renewing Judaic values in the lives of modern Jews. He is also professor of Jewish philosophy at Hebrew University in Jerusalem and has taught at colleges and universities throughout the world.

His talk, to more than 70 volunteers, staff members and guests at the San Francisco JCF building, was titled, "Is a Faith Commitment Essential to Being Jewish?" The in-service training program was underwritten by a grant from the Jack and Marion Euphrat Continuing Education Fund of the Jewish Community Endowment Fund.

"You don't have to believe in God," he said. "But you do have to be open to the story of the Jewish nation and its God. You must keep your soul open to the story."

To Hartman, that in part means not committing oneself to another religion and not allowing oneself to be defined as secular.

"We can't be a secular people," he said. "The meaning of being Jewish is bearing witness to something beyond life."

Bearing witness, or at least being open to the possibility, is the only thread strong enough to hold Jews together in the future, he said. Ethnicity, race and nationhood ultimately are not enough.

"To have Jewish continuity, you have to have Jewish content," he said. "Rosh Hashanah and Yom Kippur provide us with the opportunity to discover the moral and spiritual power present in a life of faith. Concern for the well-being of the state of Israel or the Holocaust must not become the new religion of the Jews."

The essential question of Rosh Hashanah and Yom Kippur, he said, is: "What story do you want to tell about your life? It's a story we all tell. And you can change the whole meaning of your life in a minute.

"As a community, you give each other a gift at this time of year. You give each other the opportunity to change," he added. "Tshuvah [turning away from sin] requires a certain social climate: the acceptability of change. How can you understand the Jewish people, unless you understand this? And how can you understand who a Jew is, until you understand his or her spiritual life?

He added a cautionary note. "We dare not separate loyalty to the Jewish people from loyalty to Torah," he emphasized. "To do so would be spiritual and physical suicide and the greatest threat to Jewish continuity."

Discussing the annual High Holy Day return of Jews to religious services, he said, "How wonderful it is that Jews throughout the world intuitively understand that at least on Yom Kippur they must be present in the synagogue."

But their presence alone is not enough. "At the end of High Holy Day services, we say, "Adonai hu-Elohaynu,' Adonai is our true God. Not man. Not states. Not armies. We sing it out seven times.

"This is our music. We must be open to it," he said. "To be Jewish means to listen to the music."