By Jonathan Rosen. Farrar Straus Giroux. 389 pp. $25

Iwas prepared to dislike this novel by virtue of its title alone, given the obvious falsity of the 30th Psalm's assurance that "weeping may endure for a night/ But joy comes in the morning." Neither the psalmist nor Jonathan Rosen is concerned with unpleasant reality, which dictates that a night of tears is generally followed by an even worse, puffy-faced dawn.

Nevertheless, it is impossible to avoid being charmed by what can only be described as a modern Jewish fairy tale, set on Manhattan's Upper West Side. Deborah Green, a Reform rabbi, and Lev Friedman, a science writer, meet cute in the hospital room of Lev's father. The elder Friedman has botched a suicide attempt, prompted by distress over the physical and mental damage he has suffered from a stroke. The suicide scene itself is mordantly funny, involving a plastic bag from Fairway, a noted gourmet emporium on Broadway.

Deborah is a familiar figure, the sort of busybody rabbi who descends uninvited on convalescent secular Jews lacking the foresight to check the "no religion" box upon entering the hospital. Lev is equally familiar -- a sensitive but passive-aggressive Jewish man who has already stranded one prospective bride under the wedding chuppah. They are of course made for each other.

The author, whose first novel, Eve's Apple, offered a memorable portrait of a woman with a history of anorexia, somehow avoids allowing the familiarity of his characters to turn them into stereotypes. Deborah, who wraps herself in her grandfather's tallis, or prayer shawl, before praying every morning, may be bossy, but she also has a good heart. One of the first things we learn about her is that she stoops to tie an old man's shoes on Broadway when she sees that he cannot bend over far enough to reach them.

The rabbi also displays an endearing inconsistency about religious observance. By engaging in sex outside of marriage, she breaks one of the 613 commandments mandated by Halachah (Jewish law) but observes the commandment to keep a kosher home. (A major difference between Reform and Orthodox Jews is that the Orthodox regard all aspects of Halachah as binding, while Reform Judaism treats Halachah as an ethical guide rather than a mandate. Conservative Jews fall somewhere in between.) While praying -- Deborah is an inveterate multitasker who can think about almost anything and pray at the same time -- she recalls an Orthodox boyfriend who slept with her but showed "more anxiety about the state of her kitchen -- the morning after, she'd found him sifting through the silverware to make sure that she indeed had a set for milk and a set for meat." Lev is also a likable character whose relationship to faith is far more ambiguous than Deborah's. During a harrowing scene in which he cleans up after his father has lost control of his bowels, Lev looks out the window and concludes, as 18th-century deists did, that "God, however much He might or might not exist, played no role whatsoever in human affairs."

The novel is filled with crises of faith that turn into crises of love. Deborah, after visiting a patient whose belief is shaken because she underwent a near-death experience without glimpsing her dead husband on "the other side," questions her own faith and her role as a rabbi. Deborah's mother is a psychoanalyst who regards her daughter's religious enthusiasm as neurosis, and Deborah is appalled to realize "what people like her mother must feel all the time when they contemplate the world beyond the intellectually knowable: nothing." This is a puzzling crisis of faith for a rabbi, because Judaism, unlike Christianity, has never rested on the promise or the premise that the faithful will be reunited with their loved ones in heaven. Moreover, the assumption that secular humanists (not only Jews) feel "nothing" when they contemplate the unsolvable mysteries of the universe is at once patronizing and uninformed.

The main reason that this novel is so satisfying in spite of its intellectual shortcomings is that the author's comic talent and powers of social observation are stronger than his propensity for religious pretentiousness. As Deborah presides over the contract signing that precedes a traditional Jewish wedding, an angry nonbelieving grandfather intrudes with the request that she not mention God in the ceremony. "It's all bullshit," he tells the rabbi in front of his scandalized grandchildren, who are attracted by the religious rituals that their forebear has rejected.

Lev, angry at Deborah for running away to her sister's house during her spiritual crisis, brings a non-kosher chicken back to their apartment as a form of revenge in absentia -- but he can't bring himself to pollute ritually clean dishes with the unholy fowl, and eats it out of the container. Deborah, for her part, loses her job when the elders of the congregation find out that she has been living with a man. This scene would be more plausible if Deborah were cast as a Conservative rather than a Reform rabbi. Most of the Reform Jews I know would be easily mollified by their rabbi's announcement that her wedding was scheduled in two months.

When Deborah and Lev finally overcome all of these minor obstacles and are married -- the inevitable end of all comedies -- their chuppah, sewn from two of their grandfathers' tallises, splits just before the ceremony. One is reminded that marriage is as much an act of faith as faith itself. And they lived (we hope) happily ever after. *

Susan Jacoby, a New York writer, is the author of "Freethinkers: A History of American Secularism."

Jonathan Rosen