In the old days, before Iran's Islamic revolution 16 months ago, Iranian businessmen routinely used relatives of the shah or high-ranking military or police officers to help consummate major deals needing government approval.

In revolutionary Iran, the plot remains much the same, but the characters have changed. In government offices from the Commerce Ministry to the passport bureau, Islamic clergymen can be seen acting as fixers, expediting an import permit or obtaining clearance for a new passport. And, as in the old days, Iranians take it for granted that such services are not performed without under-the-table remuneration .

Influence-peddling is but a small cog in the works of the new Iran. It is the Iran of the ayatollahs and the mullahs, the Moslem clergymen who in effect make up this country's new ruling class.

Since the February 1979 revolution overthrew shah Mohammad Reza Pahlavi, Iran's Shiite Moslem clergy has been steadily gaining political power. Now it also shows signs of becoming the country's new economic elite. Iranians increasingly are coming to realize that the mosque is where the money is.

The transition from the Iran of the shah to the Iran of the ayatollahs, as seen from close quarters over the last four years, has been marked by similar concerns on the part of those in authority.

The shah institutionalized his power, but the institutions were flimsy and, once the rot had set in, eventually came crashing down.

Today, the mullahs are moving to institutionalize their own power under the aegis of the Iranian revolution's aloof patriarch, Ayatollah Ruhollah Khomeini. Whether they can match the shah's 37 years in power is doubtful. But their steady entrenchment at the top of the new Iran so far makes a mass uprising against them -- like the one that toppled the shah -- unlikely in the near future.

Instead of another popular upheaval, the outlook for Iran now is an indefinite continuation of its slow and steady drift toward chaos. In the midst of this turmoil, the mullahs continue to cut into the authority of the secular officials formally charged with governing Iran.

The mullahs -- that is, Iran's Shiite Moslem clergymen generally -- are at the center of all the issues that this series will explore: the institutionalization of the revolution, the demise of the moderates who initiated the anti-shah movement, the repeated U.S. misjudgments on Iran and the future of a country running largely on faith.

The mullahs' emergence as the hub of a new economic order in Iran, in addition to their increasing social and political influence, is a major factor in their consolidation of power. This phenomenon tends to draw into the new system those Iranians who otherwise complain about the lack of political and social liberties.

"It's very evident that the clergy is where it's at," a Western diplomat said. "There's a strong tendency to go where the money is in this country, and people are being drawn back to the mosque as the source of money."

He cited reports of higher enrollments in theological schools in cities around the country and what he sees as a new make-do attitude -- despite ever-present discontent -- among bazaar merchants and a significant portion of Iran's middle class.

"It seems," the diplomat said, "that people would rather solve their discontent by getting what they can from the mullah system than by trying to beat the system with another revolution."

While Iran's mullahs have long been influential, especially among the half of the population that is illiterate, they never have been the hub of the system.

In fact, Iran's Moslem clergy has no centrally defined hierarchy and no established distinctions between a mullah, a hojatoleslam and an ayatollah, the main ranks in the Shiite faith. Ayatollahs achieve their status by public acclamation. Because this is so ill-defined, many clergymen have been declared, or proclaimed themselves, ayatollahs since the revolution. The result has been that this category has swelled from 22 recognized ayatollahs before the shah's downfall to more than a thousand who now claim the title.

In Shiite practice, an ayatollah had the authority to interpret the Koran and adapt Islamic law to modern circumstances.

In general, the role of the estimated 180,000 mullahs in Iran traditionally has been as custodians of public morals and values. They preach and lead prayers in mosques, officiate at funerals, run various religious shrines and receive donations to advance the faith.The money normally is used to support religious establishments, but these donations can also be channeled for other purposes ranging from public baths to charity for the destitute.

On rare occasions, such funds have been misused by individual mullahs, causing great scandals when discovered. Although Moslem clergymen generally do not take vows of poverty and occasionally have grown wealthy through economic enterprise, Islamic scholars say the mullahs' new involvement in political and economic affairs in Iran goes far beyond their traditional role.

Foundations largely under the influence of religious leaders have taken over hundreds of private companies, farms, houses, hotels, theaters, bank accounts and other assets. Worth hundreds of millions of dollars, these properties were mostly confiscated from wealthy Iranians who were executed, jailed or fled the country at the time of the revolution.

In addition, organizations controlled by the clergy are responsible for a variety of functions ranging from providing housing to the poor to arranging marriages.

The unceasing spread of clerical influence into all spheres of Iranian life since the revolution is seen as part of a strategy to consolidate political and economic power and entrench what is coming to be known as "the mullah system" before the death of Khomeini. For without Khomeini, there is no undisputed leader of the revolution, and the prospect arises of power struggle between the religious and secular figures who now jointly, though uneasily, are running the country.

"When you look at the whole thing, you see it's exactly as it was several years ago," said a senior official in a government ministry. "In the beginning when the royal family wanted to get into business, they wouldn't do it in their own names, but they were partners. With the mullahs now it's the same thing. Most of them are now going into business, but they're exerting influence."

While dissidents' accounts of mullahs' living in palatial residences and driving expensive imported cars seem exaggerated, it is evident that many have significantly improved their standard of living since the revolution.

Most of the leading clergymen in positions of power live in north Tehran, the preserve of the city's upper classes. Now even lower-class clergymen are moving into some of those formerly exclusive neighborhoods.

One well-to-do Iranian complained recently that "lower-echelon mullahs" had taken over two expensive homes in his immediate neighborhood that had been abandoned by former high government opfficials who fled the country during the revolution.

Another irony of the mullahs' new status, however, is that it has made them targets of the same type of clandestinely published but seemingly authoritative accusations that so effectively undermined public confidence in officials under the shah.

Although they cannot be verified, many Iranians believe the charges that leading clergymen transferred large sums of money out of the country.

The charges were made in lists purportedly compiled by dissidents in the Iranian Central Bank. They say they were responsible for publishing the names of leading officials of the previous government who allegedly sent vast sums abroad shortly before the revolution.

If nothing else, the latest charges amount to a public recognition of the clergy's new economic clout as a replacement for that of the political elite under the old regime.

A statement issued April 27 by the "Society of Employes of the Central Bank of Iran" and obtained by The Washington Post listed the dates, recipients, draft numbers and foregin exchange amounts of 11 transfers allegedly made between Aug. 17, 1979 and April 7, 1980, totaling nearly $100 million.

Addressed to "the heroic nation of Iran," the statement said: "Once again we deem it our duty to bring to the attention of the public reports concerning plundering of public funds belonging to the oppressed people of this land."

It said the drafts were issued with the signature of Oil Minister Ali Akbar Moinfar out of oil revenues, were designated for "promotion of Islam" and sent abroad.

The statement charged that the funds eventually wound up in personal European bank accounts of several Iranian Revolutionary Council members.

Among those named was Ayatollah Mohammed Beheshti. Three separate drafts totaling $12.35 million were listed as having been sent to the Hamburg Mosque and Islamic Center, which Beheshti ran for several years before the revolution.

Beheshti charged that the list was issued by "counterrevolutionaries and he denied benefiting from public funds. His denial was seconded by the Central Bank's Islamic society.

More sweeping but undocumented charges were contained in a separate list put out by a group calling itself "the Society of Progressive Employes of the Central Bank."

It said 40 clergymen had transferred foreign exchange and gold totaling $654 million out of the country. Heading the list was Behieshti with an alleged $79.3 million in transfers, followed by Ayatollah Khomeini's son, Ahmad, with $69.4 million. The 80-year-old revolutionary leader himself was not mentioned.

While of doubtful origin, the latter list seemed certain to arouse public suspicion about clerical wealth and raise comparisons with a prerevolutionary list in which 144 prominent Iranians associated with the shah were accused of sending $2.4 billion out of the country.

Another subject of controversy -- and a major component of Iran's new economic order -- is the Bonyade Mostazafin, or Poor People's Foundation.

Less publicity has been given to another new organization, the Alavi Foundation, which formally took over the assets of the shah's Pahlavi Foundation.

Like the Pahlavi Foundation, the Poor People's Foundation was established as a charity. But both institutions soon became the owners of major profit-making enterprises, with neither accounting adequately for the use of its revenue.

Since its previous head was assassinated by an anticlerical guerrilla group last year, the Poor People's Foundation has been run by Ali Naghi Khamoushi, a layman with close ties to the clergy-dominated Revolutionary Council.

By Khamoushi's own reckoning, the foundation now owns or has interest in 70 major industrial plants, 25 large construction firms and 30 trading companies in addition to unspecified numbers of farms, houses, hotels, theaters, nightclubs and personal property.

The foundation also owns three formerly private aviation companies and three of Tehran's leading newspapers: Kayhan, Ettelaat, and Azadegan.

In addition, Khamoushi told a Tehran newspaper recently that nearly 70 percent of current development work was being done by companies that the foundation had taken over.

According to Khamoushi, the foundation has $283 million worth of "movable property" -- including "carpets, expensive automobiles, jewelry and antiques" -- that it intends to sell to the public "so that the proceeds may be spent on the deprived."

The foundation's assets are made up of the property of Iranians associated with the shah's regime who were executed, jailed, fled the country or simply had their wealth confiscated.

Many Iranians, including some in government circles, believe the foundation has taken over much more than it has accounted for. Khamoushi has been put on the defensive by their charges that the foundation has failed to produce proper balance sheets to explain where all its money has gone.

"Everyone knows they've taken more," said one foreign economic analyst. "The whole thing stinks. There's a new system here, and it's pure banditry like the old one."

Apparently believing that the best defense is a strong offense, Khamoushi recently responded to such criticism by calling on the Revolutionary Council to turn over to the foundation still more companies and property and seeking to have various government agencies take over its unprofitable enterprises.

Another rich institution in the new economic order is the religious endowments organization, a traditional repository of clerical wealth that has grown even more affluent since the revolution. Run by Moslem clergy, it manages money and property bequeathed to it by Iranians and the income from religious shrines, notably the shrine of the Imam Reza. Among its assets are said to be fruit canning factories and the Hyatt Hotel in the northeastern city of Mashad.