These days, when Jackie Mason is ushered to the best table at the Carnegie Deli in Manhattan, the waiters bring steaming plates of lean brisket, and his tea is never allowed to grow cold. They are like show business astronomers, these Carnegie waiters, celebrating a new star on Broadway with bouquets of fresh pickles.

"Am I a hit?" asks Mason, whose one-man show, The World According to Me!, has been a critical and commercial success since it opened at the Brooks Atkinson Theatre in December. "Am I a sensation?"

In response, the waiter strips away the comedian's paper napkin. With a flourish, he produces crisp white linen and folds it silently, but meaningfully, onto Mason's lap.

In fact, it is as if a cloud has suddenly lifted for Mason, a rabbi who turned into a professional comedian a quarter of a century ago. Offers, he says, pour in like sunshine: A $250,000 advance from Simon and Schuster for a book about his life; Warner Records and HBO race to be first out with their presentations of his show; movie producers dangle deals—not just meetings and talk, but cash deals. "Anything I want to make," he says, and there is in his voice the bittersweet aftertaste of a man who has eaten his way through years of fruitless producer lunches.

Not that he trusts the visible signs—the recognition in the street, the fan mail, the endless parade of those who say they always supported him. Not that he believes the fantastic reviews and the gushing word of mouth.

"Have you heard of this Jackie Mason person?" he asks the driver of a limousine taking him to the theater. "What do you think, he's a funny guy?"

"I think you're very funny, Mister Mason," replies the driver.

He asks strangers: "Am I funny? Am I smart? Am I happy?" The probing, testing, investigating never ceases.

If Mason seems a little shaky about his star status, he has good reason. In 1964, when he was in his 30s, he stood on the verge of superstardom, but the ground gave way with the wiggle of a single finger. He was appearing on Ed Sullivan's TV show. Off-camera, Sullivan held up two fingers, a signal that Mason had two minutes to complete his stand-up routine.

Mason responded with a finger signal of his own. Whether or not it was obscene, intended as obscene or even funny, Sullivan took offense. Such was Sullivan's power that Jackie Mason was branded, at least in TV terms, as unreliable and vulgar. He spent more than 20 years in a kind of show business wilderness.

"I never starved," he says now. "I worked. I always worked. Miami. Las Vegas. Atlantic City. I made $500,000 a year. Some years I made close to a million. But this is the only business in the world if you make $20,000 a week you're a pathetic failure."

The money did not buy satisfaction. In the quest for artistic recognition, Mason sank his savings into a play, A Teaspoon Every Four Hours, a critical flop that he says was popular with audiences. Then he financed his own movie, The Stoolie, a commercial flop that he says was a critical success. "I was frustrated," he admits. "I went into debt. I knew that I should have been a superstar. You didn't know this?"

There is a price a man pays for spending a lonely life on the road. You can read it between the lines in the setting of his Park Avenue apartment. The rooms are expensive and professionally decorated, but there is no table on which to eat and no comfortable chair in which to rest. There are phones and big-screen televisions, but nothing personal, nothing human.

There is something else—a kind of permanent detachment. He changes girlfriends the way he changes hotel rooms. "Frankly, I never believed in marriage," he declares one night after a show, sitting where he feels most comfortable—in a bleak theater-district coffee shop. "I am not the kind of person who wants to be honestly responsible for another person. It's total hypocrisy. People have children but they have no time for them. Disgusting. Tell me, would you open up a store and not give it any time? This is what parents do with children."

On this particular night he is supposed to meet "the top people" from the William Morris talent agency. They are taking him to dinner at Mr. Chow, where they will stuff him with fine food and feed his hungry ego and promise him the moon. Yet here he sits in a dim coffee shop, watching the door. Finally, in walks a woman with blond hair and a tight dress. "There you are!" he cries, leaping out of his chair. "I would like you to meet my physical therapist," he announces.

Someone reminds him of the agents waiting at Mr. Chow. Everyone leaps into a car, including the blond therapist. There are heated whispers, and this outburst from the therapist in the backseat when she learns Jackie has another blonde waiting at the restaurant: "What do you mean, there's another blonde!" At Mr. Chow, he leaps out of the car, leaving behind the now stranded therapist.

On the night of a recent blizzard, most Broadway shows are playing to empty chairs. But not at the Brooks Atkinson. The 1,100 seats are almost all occupied. Up on the stage dances this short (5'7"), stumpy (170-lb.) new megastar. He is making fun of Sylvester Stallone, status symbols, politicians, Jews, gentiles, himself.

"It's not my nature to talk bad about people," he says after doing nothing else. "Take Ronald Reagan. I don't talk bad about the President. Have you ever seen such a happy President? You know why he's so happy? He can't believe he got the job. It's not his field. He don't get involved in politics. This is a whole new type of President.

"He ran against Mondale, and all Mondale said was the deficit, the deficit, the deficit. Ronald Reagan said the most brilliant thing. He said, 'There's no deficit.' Everybody said, 'But there is.' He said: 'So there is.' "

On a stage, Mason seems to shed weight and worry. And years, although the question of his age is touchy; he insists that he's 51 in spite of good evidence that he is 55. There is a protective conspiracy in the family to hide Jackie's birth date. His brother, Rabbi Bernard Maza, who is quite willing to say that Jackie was, from youth, a comic and an intellectual nonentity in the family ("You didn't know he existed") is unwilling to reveal Jackie's age. "We don't believe in numbers," the rabbi explains. "It's bad luck to count your blessings by numbers. But getting back to Jackie's comedy. Now we think he's a genius. Then...?"

Jackie Mason was born Jacob Maza to a rabbi who came from Minsk and eventually settled on the Lower East Side of Manhattan. "My father, Eli, and my father's father, and my father's father's father—as far back as anyone can remember, all rabbis," says Jackie. There were two younger sisters (Gail and Evelyn) in addition to three brothers (Joseph, Gabriel and Bernard). "My three brothers all became rabbis, and I became a rabbi. I had no choice. It was unheard of to think of anything else. But I knew, from the time I'm 12, I had to plot to get out of this, because this is not my calling. I am not so sure about God, but I knew for certain that I worshipped the young girls, and this could get me into big trouble."

Jackie's gift for satire appeared relatively late in his life. "He was always the most serious person at the table," says his sister-in-law Malka Maza. "He only wanted to talk politics." Says Jackie: "My brothers were all brilliant and I was a shmuck. Every time I opened my mouth they told me to shut up. So I hung out with guys on the corner—Sol, Nat, Irving. Compared to them I was a genius."

During summers in the late 1950s, Jacob Maza became Jackie Mason and went to work in the Catskill Mountains borscht belt, the vineyard of Jewish comedy. First he was a waiter.

"Twenty minutes, at the Pearl Lake Hotel," he recalls. "I broke all the dishes. They made me a lifeguard. But I can't swim, I told the owner. 'Don't tell the guests,' he says."

When his father died in 1959, Jackie Mason ended his work as a rabbi and became a full-time comedian. He enjoyed his job as a comic, but always knew it would not have met with his father's approval. "He only approved of studying and learning," says Jackie.

About a year ago, he saw Dick Shawn doing a one-man show in a legitimate theater in Los Angeles. His manager, Jyll Rosenfeld, thought that this was Jackie's natural showcase. Mason became a comic cult. Tributes from Mel Brooks, Carl Reiner, George Burns and Neil Simon did not hurt. Finally, he took his shtick to Broadway.

Why did the act work so well in a legitimate theater when he's been doing the same material for so many years?

"It's like putting a painting in a museum," he explains. "Now it looks like something."

He is in his dressing room, still wearing his stage makeup. The stage manager brings flowers and mash notes. A woman who spurned him a year ago waits downstairs, hoping he'll forgive and let her buy him dinner. Jackie Mason gazes intently into the makeup mirror as if it will reveal some secret of success that has eluded him all these years. He says, almost to himself, "Why did it take so long?"