Arnold Rosenberg was trying to write some margin notes for a seder when he came up with a disarmingly basic question:

What did the prayers in the Haggadah mean? He wasn't just after their literal English translations. What was their function in a modern person's life?

Some of the books he dug up provided history and scholarship. But none gave detailed examinations of the meaning behind Jewish prayers.

Four years later, the 46-year-old San Francisco attorney offers such answers in his own book. "Jewish Liturgy as a Spiritual System" explains prayer by prayer how Jewish worship works.

"We know the prayers originated in different times and different places and contexts," Rosenberg said in a recent interview. "But over the years, they were put into a sequence and a form. I asked the question: When these largely unknown individuals who redacted the prayers put them into this form, what must they have had in mind?"

Working with more than 200 scholarly sources and original texts, "what I found was that the Jewish prayer service is really a sequence of prods and aids to the minds of worshippers to push them through a series of altered states of consciousness," Rosenberg said.

"You're supposed to leave Jewish prayer services more inclined to do good and less inclined to do bad than when you came in, and this is achieved gradually, not in one step."

The steps the prayers represent are elucidated in a table at the back of the book. For example, in the Blessing After the Reading of the Psalms in the morning service, one should be able to visualize the events during which David, Nehemiah and Moses uttered their praises, Rosenberg writes.

These include the gathering of materials for the First Temple, the end of the first festival season after the return of the exiles to Jerusalem and the Israelites' salvation at the Red Sea.

The next prayer is the Nishmat, the Blessing of the Song, during which "we feel the relief one experiences when an emergency has ended," Rosenberg writes.

"One interesting thing about this approach," Rosenberg said of these progressive mental states, "is that frankly it isn't even essential for prayer to have meaning to an individual or that the individual believe in God. If the purpose of prayer is to fortify ourselves, to change our minds, then we have the capacity to do that ourselves."

Rosenberg was not always religious. Raised Conservative in Rochester, N.Y., he did not attend synagogue at all while attending Harvard Law School and after he began working as a poverty lawyer and then a labor lawyer.

He moved to San Francisco in 1983, and around that time started gravitating back to Judaism, eventually attending the city's Congregation Beth Sholom. But he was looking for something more from the services.

"I realized that I could no longer be satisfied just relying on a sense of nostalgia or a sense of comfort that the synagogue environment could convey," he said. "It was no longer satisfying to me just to enjoy the melodies. I wanted to know why I was praying and what the significance of the prayers was."

He discovered that the process of prayer itself brings one closer to God in everyday life.

"A person who has prayed in the way that I discuss in the book," Rosenberg said, "who has used prayer as a device to achieve a quieter and stronger state of mind, can sit in a traffic jam and still retain that state of mind — and by virtue of that, alleviate frustration and the temptation to scream and yell at the next driver, which we all experience."

People in the late 20th century may be under increasing stress and life may be more complicated, Rosenberg said. But "to have prophetic consciousness is still possible in the modern world."