The Seventh-day Adventist Church, founded in the United States more than a century ago after a prophesied second coming of Christ failed to occur and now a worldwide institution headquartered in Takoma Park, today faces what may be the most serious crisis in its history.

Already divided by theological differences, the church has been plunged into a financial tangle that may cost it and its members millions of dollars and, conceivably, ensnarl it in legal battles.

The financial problems were precipitated by the bankruptcy suit filed last month by Dr. Donald J. Davenport, a California physician, who relied on his credentials as a faithful Adventist to solicit the investment of millions of dollars in his real estate empire. Davenport's preliminary bankruptcy petition listed 27 Adventist institutions among his creditors, and more than 200 individuals, the majority of them fellow Adventists.

Also on the creditors' list are more than a score of banks, including some of California's largest, whose attorneys are currently studying whether there might have been anything in the financial relationship between Davenport and the church or its leaders that would warrant legal action. No such action has been taken to date.

The Davenport case comes at a time when the church is embroiled in theological differences that pit church administrators against some pastors and Bible scholars. In recent months several well-known pastors have been stripped of their ministerial standing, about 50 congregations have left the denomination, and some members report an atmosphere of fear and suspicion has invaded the church, which traditionally has fostered strong bonds of fellowship.

To outsiders, the Seventh-day Adventist church is a church of paradoxes:

Founded by a woman, it steadfastly has refused to ordain women to the ministry in the contemporary church.

One of only three major Protestant churches native to American soil (Mormons and Jehovah's Witnesses are the other two), nearly 83 percent of the church's present membership of 3.83 million live in other countries.

Central to Adventist belief is the conviction that Christ soon will return,marking the end of the world as we know it. Yet the church hierarchy long has been deeply involved with this world's financial affairs.

The massive health care, publishing, insurance and health food enterprises of the church's international governing body, the General Conference, have earned it a listing in Standard and Poor's, the only church to be included, according to a spokesman of the closely followed information service on big business. In 1979, the relatively small church reported total assets in excess of $4 billion.

One reason for Adventist attention to money is the church's conviction that it has been appointed by God to spread its distinctive message throughout the world. Sizeable amounts are needed to support the work of its worldwide force of 93,000 ministers, evangelists, missionaries and other workers.

This church of global reach grew out of a mid-19th century prophecy that Christ's promised return to earth would occur on Oct. 22, 1844.

Among the tens of thousands who were disappointed when the appointed time came and went, were James and Ellen White. Further study of the highly allegorical portions of the Old Testament Book of Daniel, reinforced by heavenly visions, convinced Mrs. White that the prediction had been only half wrong; that while Christ had not returned to earth in 1844, he had moved from one heavenly sanctuary to another in order to begin His "investigative judgment," sorting out the unrighteous from the righteous, determining who would be saved on Judgment Day.

Following Mrs. White's admonitions, Adventists live by a strict moral code. They abstain from the use of alcohol, tobacco, coffee and tea. They operate thousands of free, widely acclaimed stop-smoking clinics to help persons outside the church kick the habit.

Church members wear no jewelry, not even wedding rings. For women, "any use of cosmetics that becomes apparent is considered an overuse," a church statement warns.

Vegetarianism is strongly encouraged. Adventists gave the world corn flakes, a recipe developed by W.H. Kellogg in response to Ellen White's emphasis on cereals. An enterprising patient in Kellogg's Battle Creek sanatorium, C.W. Post, later founded his own cereal empire on a reproduction of Kellogg's crunchy innovation.

The church today owns and operates 47 health food factories around the world, turning soybeans and other vegetable protein into analogs of ham, steak or turkey. In 1979, the church's food factories racked up $188 million in total sales. A ready-to-eat breakfast cereal called Weet Bix, produced by the church's Sanitarium Foods of Australia, has become the best-selling cereal in that country.

Adventists give their church massive amounts of money; well over half tithe 10 percent of their income. Tithed funds are earmarked for pastors' salaries and pensions, for the support of regional church bodies known as conferences and unions, and for mission work. Additional offerings are required to finance the local congregations, to build and maintain schools, to support a massive program of world missions and other special projects.

Adventists regularly lead the list of per capita giving of Christians in this country to their church. Last year they averaged $743.71, and that did not include donations to the church's emergency relief fund. Nor did it include the tuition paid by Adventist parents to send their children to church-run schools, the largest Protestant private school system in the world.

It is not uncommon for Adventists to turn over 20 percent of their income each year to their church. "It is unbelievable the way Adventists give," said Elder James Londis, pastor of Sligo Adventist Church in Takoma Park.

In addition to tithes and offerings, which last year netted the church $425 million, the church has an extensive trust program. Virtually every regional unit of the church in this country employs full-time staff persons to persuade members to invest their savings in church-operated trust funds from which they will receive income as long as they live. On their death the amount reverts to the church.

Some of the money invested in Davenport's ventures came from these trust funds. The trust funds are operated by the separately incorporated Conferences and Unions of the church. Recent court decisions indicating that a national denomination can be held responsible for the financial shortcomings of one of its parts has raised the specter of multiple lawsuits against the General Conference in the Davenport affair.

A spokesman for the church said last week that officials expect to know sometime this week the full extent of investments by units and members of the church in Davenport's real estate empire. Preliminary estimates put the total he owed to his creditors in excess of $40 million.

For years, some in the church had warned against investing in Davenport's operation.

Some in positions of authority in the church did heed the warnings. More than two years ago, Kenneth H. Emmerson, then treasurer of the General Conference, wrote to a church official that he had warned Loma Linda University, the pride of the church's academic institutions, that it "should have nothing whatsoever to do with Dr. Davenport or any of his financial 'schemes.' "

In his letter, which since has been widely circulated throughout the denomination, Emmerson promised that at a forthcoming meeting of treasurers of Adventist Conferences and Unions, "We are going to strongly urge, in fact we are going to do everything in our power to make it imperative that the brethren begin to liquidate any connection and investments they have with the Doctor."

Why Emmerson's advice of April 1979 went unheeded, why so many Adventist institutions still were listed as creditors of Davenport in his initial bankruptcy petition filed last month, remains a mystery.

Church leaders remain close-mouthed. The General Conference has directed its Conferences and Unions not to talk to the press about the matter but to refer inquiries to the General Conference.

Neal Wilson, world president of the church, has refused repeated requests for an interview. His office refers inquiries to James E. Chase, an affable pastor who heads the communication unit. Chase's response to questions about the Davenport affair: "Testimony is being taken, work is going on. Beyond that I can't comment."

Among the faithful there are growing indications of dissatisfaction. "The Adventist Church worldwide is not being told the true story by our church leaders," complained Dan Ipes of Columbia.

Ipes, an Adventist pastor and son of a pastor, feels the church leadership is not being open enough. "A lot of local pastors are really sweating on this," he said. "I want the church to come clean. If we made a mistake, then let's say we made a mistake . . . This is my church. I've got a lifetime investment in this church."

The Davenport bankruptcy comes at the time when the church is reeling from theological controversies. Two years ago, an Australian pastor and biblical scholar, Desmond Ford, publicly challenged Ellen White's "investigative judgment" interpretation of the Book of Daniel, namely that since 1844, Christ has been investigating the lives of Christian to determine which are deserving of salvation.

Ford espouses the orthodox Christian view of salvation by grace alone: that by His death on the cross, Christ atoned for the sins of all mankind; that Christians attain salvation not by good works but by faith in Christ; that there is no biblical basis for belief in investigative judgment. If the argument seems arcane to nontheologians, it strikes at the very heart of Adventist distinctiveness and, for some, the church's very reason for being.

Last August, a consultation of Adventist scholars and administrators gathered in the Rocky Mountain retreat of Glacier View, Colo., to ponder with Ford the theological questions he raised, questions that "one person after another has been raising . . . for 75 years," according to Dr. Raymond F. Cottrell, scholar and widely respected elder statesman in the church.

At the end of the three days of intense debate, a committee of the General Conference recmmended Ford's removal from the ministry.

The action against the charismatic if controversial Ford sent shock waves through the church, particularly the clergy. The shock was to be repeated two months later with a similar dismissal from the ministry of Walter Rea, a Long Beach pastor.

Rea's devotion to the founder of his church had led him to scholarly research on Ellen White's writings. To his dismay, he began to discover that vast sections of her works were not, as Adventist teaching had it, directly inspired by God, but lifted without attribution from popular religious writings of her day.

Church authorities acknowledged White's "borrowings."

"The fact that Mrs. White made wide use of other sources and creatively used Protestant historians in preparing her works does not negate her inspiration," said Harold Calkins, president of the Southern California SDA Conference, which unfrocked Rea.

What seemed to rankle was that Rea had embroiled the church in public controversy by discussing his findings in the press. The decision to expel the 58-year-old Rea from the ministry, Calkins said, was "based on the negative influence of Rea's conclusions circulated worldwide." Both Rea and John Dart, The Los Angeles Times' religion writer who wrote the syndicated account of Rea's findings, insist that it was Dart, not Rea, who initiated the article.

Like most churches these days, Seventh-day Adventists suffer the theological tensions of conservative-progressive polarization.

Writing in the unofficial Adventist quarterly, "Spectrum," Cottrell observed that "until about 1940, practically all Adventist Bible study relied on what is known as the proof text method. Today, most church administrators still follow that method, whereas almost all Bible scholars follow the historical method," which involves going back to the original languages as well as a study of the historical, literary and social context of the particular verses.

Two statements made at Glacier View highlight the difference. Cottrell cited the affirmation of a church administrator at one of the sessions: " 'I search the Bible for evidence that our message is true,' " In contrast, he continued, "a majority of the Bible scholars present would have said: 'I search the Bible to hear what it is saying, in order that my presentation of our message may be true to the Bible.' "

It is the difference, Cottrell continued, between viewing Adventist tradition as "the norm for interpreting the Bible rather than the Bible for Adventist tradition."

The church's continuing emphasis on education has produced growing numbers of pastors and Biblical scholars with advanced degrees from Harvard, Princeton and Chicago, men committed to a scholarly approach to the Bible. The tension between the scholars and the administrators can be expected to increase.

Earlier this year, Smuts Van Rooyen, dean of the church's only graduate seminary, at Berrien Spring , Mich., was dropped from the faculty because of views similar to Ford's.

Pastors and theologians interviewed for this article have, almost to a man, been unwilling to be quoted by name. "There's such a witch-hunt going on," explained one man apologetically. "We're all a little hyper."

"Most scholars have to be very quiet or else they'll lose their jobs," explained Ford, who now is working for the Good News Unlimited Foundation in Sacremento, which he characterized as an "evangelistic resource center." Ford added that "more and more men are being threatened."

In June, 17 teachers from seven Adventist colleges and universities met unofficially in Atlanta to discuss what could be done about what they called "the current divisiveness within the church."

In their "Atlanta Affirmation" they deplored "the present climate of distrust and alienation" they saw in the church and said that "well-meaning attempts to respond creatively to theological questions now confronting Adventism have been interpreted in some circles as jeopardizing the integrity of the church and its message."

They appealed to "teachers, pastors, administrators, and other church members to attempt now to stop the polarizing process that threatens our unity and future as a movement . . . ."

According to a well-connected scholar in the church, who asked not to be identified, several of the men who signed the generally conciliatory Atlanta Affirmation since been severely criticized and one has had a speaking engagement canceled because of participation.

The controversy over doctrine is not just a squabble among a handful of theologians. In his baccalaureate sermon to the summer graduating class of Columbia Union College in Takoma Park earlier this month, Dr. Lloyd A. Dayes, associate professor of surgery from Loma Linda University, told the students: "God does not want you to be trapped by the doctrine of the Adventist Church because God is larger than the doctrine." He was greeted with rousing "Amens."

Although he would not talk to a reporter about the church's theological crisis, church president Wilson, writing in the Aug. 6 issue of the church's "Review and Herald," which goes to all members, did note "a disproportionate amount of time consumed in trying to untangle the theological questions and doubts that have been indiscriminately scattered abroad." Wilson has called a high level conference next month to address these issues.

Church spokesman Chase took a positive view of the theological controversy. "These things will not stop the Adventist Church," he said. "The church will go right on."