COLUMN ONE : For Saudis, Sands Are Shifting : Belt-tightening is the byword after years of frantic growth fueled by oil. Having embraced the modern world, many now fear being trapped by it.

The parking lot adjoining the Grand Mosque boils into an urban stew by midday. Bulldozers belch clouds of dust from the pedestrian plaza under development next door. Cars of downtown shoppers crawl across the construction debris. And, defying the scorching heat five times a day, a swarm of Muslim faithful stream out of their offices to the mosque to pray.

But on one Friday last month, the bulldozers and the cars were herded aside, and a line of police officers formed a human barricade near the center. Presently, six men were led in, nudged to their knees and, with a few swift swishes of a sword, delivered of their heads.

The loudspeakers of the mosque that usually sing the call to prayer recited the men’s crimes: highway robbery, murder, drug trafficking. Somewhere near the back of the crowd that had gathered someone shouted “Al Hamdulillah!” (Praise God!) The rest of the onlookers began clapping quietly.

“It sounded a lot like the applause after a good chip shot in golf,” said a Western diplomat, who watched this 15-minute dispensation of Islamic justice.

There was little need for spectacle. Already this year, executions under Saudi Arabia’s Koranic law are more than three times the number last year. The number of severed hands--Islam’s punishment for thievery--is also up.

While a number of factors may be at work in swelling the swordsman’s business in downtown Riyadh, sociologists and government officials here say a rising wave of thefts and drug-related crimes points up the isolated desert kingdom’s growing difficulties in holding the outside world at bay.

For nearly two decades, Saudi Arabia was a Middle Eastern outpost of the American dream, an oil-fueled wonderland where entire cities sprang up along empty coastlines, where six-lane highways were laid over the old camel routes almost overnight and spectacular new international airports brought in millions of foreign workers to help build a new country.

The vast pool of crude oil under the desert floor was earning more than $100 billion a year for the few million Saudis who had wandered largely penniless across the Arabian peninsula only half a generation before. Because it could afford to, Saudi Arabia, the guardian of Islam’s holy cities of Mecca and Medina, remained--in the midst of a dizzying economic boom--a haven for one of the strictest Islamic societies in the world.

Despite the veritable siege of Western workers, Saudi Arabia has remained a country without alcohol, without public entertainment and without substantial contact of any kind between unmarried men and women. Women emerge from their homes only heavily veiled in black and are not permitted to work except with other women. The Koran and Islam’s sometimes harsh law, the sharia , remains the country’s only constitution.

But now, weathering a devastating slump in world oil prices that has diminished petroleum revenues to less than one-fifth of what they were, the fabled oil sheiks of the Arabian desert are learning the fine art of belt-tightening--and all that accompanies it.

Government spending has been cut by half, eliminating, for instance, the large, free stipends that Saudi undergraduates studying abroad once received and substantially slowing the flow of foreign aid to poorer neighbors throughout the Middle East. Western contractors who earlier cashed in on the building boom are now left waiting months or longer for their money. The bountiful Saudi budget is running a deficit for the sixth straight year--and many Saudis have begun to wonder privately whether the miraculous desert kingdom can ever be the same.

“We took the West as our model, and now we are trapped by it,” explained Hani Draye, a young writer and government employee and one of several youthful Saudis who, in interviews over the past month, expressed fears that economic realities--the need for many women to work, for example--and a growing generation of Saudis who expect more than the government can deliver threaten to change forever a country whose religious traditions span 13 centuries.

Nearly 65% of all Saudis are less than 25 years old, and nearly all of them, Saudi sociologists say, grew up in an era when the government provided not only free tuition but a monthly salary for all university students and well-paying government jobs after graduation. Now, the government has said it can no longer afford to be the employer of last resort, and though the unemployment rate remains nominally non-existent, Western analysts say it cannot stay that way for long.

One diplomat said he received a report that the criminals executed last month had left notes with their victims declaring they were university graduates without jobs.

“We were forced to do this,” the notes reportedly said.

“I’m a nomad, from a tent,” said Mohammed Oteibi, who went from being a sheep-herding Bedouin to a doctorate-level sociology professor at King Saud University in a matter of a few years. His father still lives in a tent near the gleaming Saudi capital of Riyadh, but Oteibi worries that he doesn’t have the same ready answers for his children that his father had for him. His 19-year-old daughter wants to go abroad alone to study; Oteibi, who studied himself in the United States, says no, not without her brother, or a husband, to look out for her. But he can’t explain exactly why.

“You are Saudi,” he says finally. “No matter whether you went to the U.S. or Japan or Mars. You are Saudi. And you should do as they do.”

Maha, his daughter, fumes. Oteibi frets.

“There is very rapid change, and for me, it’s scaring me, to tell the truth,” he says. “We used to have values, we used to have a lot of things, and we are missing it. The sky rained a lot of money on this area, but the social fabric is fading away.”

Saudi Arabia is a place where the modern and the ageless are in a state of perpetual collision.

Just a few blocks from the parking lot of the Grand Mosque is old Riyadh, or what can still be glimpsed of it. Ancient mud-brick houses have been left standing, but entire rows have been blocked by modern office towers and shopping centers built directly up to their front doors.

On the outskirts of the city, men drive out to the desert’s fringe at twilight, pitch a tent and pass the hours as Saudis for hundreds of years have passed their evenings: sipping tea, playing cards, talking--but now, often, over the drone of a battery-operated television.

One recent afternoon, a Saudi cab driver careened madly down a mountain highway, the traditional red-and-white head scarf that all Saudi men wear streaming out the front window. Just at sunset, he threw the car over to the side of the road, skidded to a stop and leaped out.

Rushing over to a roadside faucet, he began furiously washing his hands, face and feet. It was prayer time, one of five times during the day when life all over Saudi Arabia comes to a temporary halt. Shops close. Offices empty. Television soap operas are interrupted with the drone of Koranic verses. After touching his forehead to the desert sand as the sun set over Mecca, the cab driver strolled back to the car, the last of his prayers still on his lips.

Saudis are constantly faced with the challenge of living as 7th-Century Muslims in a country approaching the 21st Century. One man, for example, last month wrote to an Islamic adviser in the newspaper to find out how, in the age of modern jet travel, one can be sure he is actually bowing in the direction of Mecca in mid-flight.

Worried another: “I laugh often and much. I am told that this is forbidden in Islam. Is it true?”

(True, he was advised. “Too much laughter,” the Prophet Mohammed once said, “causes the heart to die.”)

Only now, with the economic recession, are Saudis starting to catch their breath. After years of total directional confusion, for example, Riyadh, a city of 1.5 million people, has just gotten round to a project to name its streets and give all houses a number. The project has been delayed by lengthy arguments over precisely what names the streets should have.

In the sprawling port city of Jidda, former Mayor Mohamed Said Farsi is credited with preserving a large section of the city’s historic downtown while undertaking some of the most phenomenal construction projects ever attempted by a municipal government.

As a close friend of Saudi King Fahd, Farsi had a virtual blank check throughout the 1970s to shape the city, and his wand was sweeping. Four thousand kilometers of roads, including the largest seaside corniche in the world, were built in 10 years. Farsi wanted an open-air museum along the beach, and a museum complete with the works of painter Joan Miro and sculptor Henry Moore appeared.

Swept up by his own grand vision, Farsi declared that all the houses in Jidda should be white--to the consternation of many longtime Jiddans, who thought their houses should remain as they were. People were even more irritated when Farsi, taken with the idea of building a new road, would sometimes take over their property and build the road without notifying them first.

“If you inform people so far (in advance), they would never allow it,” he explained in a recent interview. More important, he said, was getting the roads finished so that new roads could be built after them.

“You see,” he explained, “if I do this road in two months, I have time to do other road after two months, while you still have money. If you don’t do it in two months, you spend only 2 million riyals in one year. If you finish in two months, you can spend 5 million riyals in one year.”

Farsi and his dream for Jidda embody the whole sense that permeated the Saudi boom years, a sense of urgency, of the need to catch up fast.

“Everything was fast, because time is very important to us,” he said. “I remember I was at an embassy dinner one time, and a man asked me, some cities have electrical problems, some telephone problems, some sewage. What is your problem? I was thinking, and I told him, my problem is time.”

It was that being in a hurry that led Saudi Arabia to import huge numbers of foreign laborers, technicians and contractors to build and run the new factories; drivers, houseboys and waiters to hold down domestic jobs while young Saudis were off at the university.

Even now, only 7 million of the 11 million people who live in Saudi Arabia are Saudis; the rest are foreign workers who are sending large sums of valuable hard currency back home and--even more troublesome for the Saudis, government officials and sociologists admit--are, for all their alien Western ways, the ones who keep Saudi Arabia running.

A key aspect of the country’s just-completed five-year plan is both to diversify the economy--develop ancillary industries to make Saudi Arabia less dependent on exporting crude oil--and to replace much of the foreign work force with locals, a process known as “Saudization.”

To a large degree, it is beginning to work. Saudis now hold most top management positions at key Saudi companies. Aramco, the American oil company that launched Saudi Arabia as the world’s largest exporter of oil, became wholly Saudi-owned last year. Technical schools have begun turning out Saudi graduates bound for mid-level jobs.

But the process has been painful, many businessmen and government officials said in interviews, because young Saudis still expect a university degree--and a white-collar job to go along with it.

Said A. M. Alsadhan, secretary general of the Civil Service Council, which helps oversee the country’s mammoth civil service network: “The impression is that the young Saudi may not be willing to accept the conditions of the working environment in the private sector. He doesn’t want to work long shifts, he doesn’t want to work on Thursday (the first day of the Saudi weekend), he doesn’t want to be scrutinized.

“But these are a lot of assumptions that have never been supported by any pragmatic study that you can depend upon. There is only one way to find out, and that is for Saudization to roll in. It needs a lot of courage, and it needs a lot of loyalty as well, believing that this country has given a person so much that he has to give back royalties, so to speak.”

A young Saudi industrialist, educated in the United States, said he has second thoughts about hiring fellow Saudis who have never traveled abroad: “How am I going to communicate with this guy? He spends two hours praying, and he doesn’t work,” he said impatiently.

“On the other hand,” he said, remembering how much he changed during his years in America, “am I going to be accepted? . . . The lower middle class are trying their best to communicate. They speak some English, and they try to somehow be superficially in touch with the real world, but when it comes to real communication, sharing ideals and views, it’s very different. But the bottom line is, you can either by co-opted, or you can be alienated. Because these two forces will never meet.”

There is an almost mystic stillness to the desert night air. It is heavy and hot and, here in the mountains above the Red Sea, sheltered from the salty breeze blowing in over the ports below.

On nights like this, Saudi men often drive out to one of the coffeehouses nestled in the shelter of the rocky hills--quiet, open dens covered with Oriental carpets and soft pillows where, for hours on end, they sip mint tea, smoke a dizzying molasses brew from a gurgling water pipe and philosophize.

“The Third World surrounds us. We are surrounded by idiots. And I sometimes think we are idiots, too,” a young Saudi banker said on a recent night over coffee.

“Everything you see, it was built by foreigners, and they go home. How are we going to learn if we don’t dirty our hands? We don’t have Saudi plumbers, we don’t have Saudi electricians, this is the problem. You see a lot of people working for the government, they are not qualified for their jobs. They come to work at 8 and open the paper, and at 12 they close the paper and go home. Because there is nothing to do.”

Leaning forward, and looking around to make sure no one was listening, he grabbed his white head scarf and long white robe. “Look at this,” he hissed. “We look like ghosts, and the women are in black. Why? I want to see it progressing, and our reputation is going down the drain. And it hurts. Sometimes, I’m outside, and I cannot say I’m a Saudi.

“I go out,” he explains, “because I have to. I can live here for one, two, three months, but I want to see a normal life, normal people. So what I do is I work hard two or three months, I take a vacation one week, 10 days, I go out, I do whatever I want, I come back. Another frustration period. I work hard, make money, I go out again. Sometimes I’d just like to go to a movie; sometimes I’d like to go to a park. I’d like to have a choice. But my choice is to get bored.”

Government officials admit privately they must accommodate frustrations like these. But they also say they must balance that against a rising tide of conservatism among many Saudis who have not traveled abroad--and who are likely to turn increasingly to Islam as a refuge in a time of mounting economic uncertainties.

“I think things are getting better,” said Abdulrazag A. Algain, assistant deputy minister for planning. “As a machine, nobody will stop it. But we don’t like to challenge everybody, to challenge religion. After all, they are our fathers and our brothers.

“Planning isn’t easy work,” he said. “You have to plan, you have to dream; some of your dreams end up a nightmare. There are some things that happened here too fast. But we are not sorry. We were in a panic, you know. Everybody was in a panic. The government was in a panic. We wanted to build our country. We had the money to do it. But now the slowdown has given us a chance to think.”