The Catholic University of America installed a Jesuit as its 12th president yesterday, affirming the intention of the historic university in Northeast Washington to maintain its liberal arts and religious traditions.

Catholic still requires all of its students to take courses in theology and philosophy. Most graduating students must pass comprehensive examinations in their major areas of study, a requirement that has stood since the 1930s. Mass is offered in the campus dormitories, none of which is coed.

And while some Catholic universities have shied away from such things as prayers that might not seem ecumenical, Catholic University installed the Rev. William J. Byron as president with prayers that clearly reflected the unique doctrines of the Catholic church.

"It is a compelling conviction of mine that a university without a faith commitment is an incomplete university," Byron, flanked by red-robed bishops, told an audience of 3,000 who attended his installation beneath the gold mosaic dome of the National Shrine of the Immaculate Conception.

"Horizons here are lifted by faith, expanded by hope and encircled with love," he said. "In such an environment, we daily demonstrate the compatiblity of faith and reason."

The 55-year-old Pittsburgh-born economist, who has been president of the University of Scranton and dean at Loyola University in New Orleans, pledged to bring growth and financial security to the school, the only Vatican-chartered university in America.

Byron replaces Edmund D. Pelligrino, now a professor of medicine at Georgetown University, as president. Although he is the first cleric to head the school since 1969, his installation signaled no sharp departure in the university's direction. This sprawling complex of Gothic-style buildings situated in Brookland, a largely middle-class neighborhood that is about 90 percent black, has seldom changed for the sake of change.

"We never gave in in the late 60s at the time of student upheaval mainly because our students didn't want it. They came here looking for a liberal arts education," university Provost John J. Murphy said in an interview earlier this week.

Founded in 1884 by the American bishops as a graduate school for priests, the university remains today the country's foremost school for Catholic religious studies, even though priests and nuns now represent less than 10 percent of the the students and faculty.

The school is part of a large Catholic enclave in Northeast Washington that also includes the Shrine -- the nation's largest Catholic church -- a monastery and Trinity College.

It is also the only university in America that offers "pontifical degrees," conferred by the Vatican, in philosophy, theology and Church law.

Because it is a relatively small private university (7,057 students), Catholic has tried to showcase certain disciplines and programs, Murphy said, instead of trying to be all things to all people.

It has a renowned graduate school for social work. Its drama program has produced such graduates as Jon Voight, Helen Hayes, Walter Kerr and Mart Crowley. Its Center for National Policy Review has been extremely active in championing civil rights.

It has research centers studying youth development, the family and aging, among other areas.

But what separates intellectual pursuit at Catholic from that of other liberal arts schools, say its leaders, is that the faculty is expected to point out to students the moral dimensions of the subjects they teach, be it biology, politics or physics. Murphy said that in engineering, for example, he expects professors to raise the moral arguments for and against the use of nuclear power.

Two-thirds of the entire student body is Catholic, including 90 percent of the 2,920 undergraduates. Most of the students come from white, ethnic, working or middle-class families. More than half the undergraduates attended private or parochial schools in the Northeast. The average student scored about 100 points above the national norms on college board tests.

Yet, says student government leader Paul DelPonte, they are as likely to be opposed to abortion as to human rights violations in El Salvador and nuclear proliferation. The Peace Studies Club and Social Concerns Committee are among the most popular student activities, he said.

Alrie McNiff, a junior and communications major, said she believes many students are attracted to Catholic because it is in the nation's capital and offers a liberal arts education within a Catholic framework.

"You might find another school that offers the same academic standards, but would not provide the other things, like personal guidance," she said.

Many students work to help pay for their education. Tuition is $5,750 a year. Room and board bring costs for some up to $8,000.

"We're the kids of working-class families; the generation that's supposed to make it," said Chris Heimann, a senior political science major. "Our parents have worked all their lives so their kids could go to college and be the professionals they could never be."

Heimann and others say they sometimes feel a certain hostility from young blacks in the neighborhood. "You get the feeling they think we're a bunch of rich white kids taking over their neighborhood," said Robert Russo, a student leader.

However, Robert Artisst, president of the Brookland Civic Association, said he believes "the relationship of the residents and the university has been rather compatible."

Over the last six years, Artisst said, the university community seemed to take more interest in neighborhood affairs as the problems of Brookland -- crime, transportation and ecomomic development -- began to encroach upon the university as well.

Catholic shares the problems of many private universities nationwide, according to Murphy. College board scores are declining; faculty salaries are low, and the university is finding it difficult to hire young faculty members, he said.

The university, which has an annual budget of about $50 million, lacks the large endowments of many private schools and depends heavily on tuition and an annual contribution of some $3.5 million that the bishops collect from the Catholic parishes throughout the country.

University officials say additional funds would be used to offer more scholarships, particularly to minority students, offer more fellowships and expand research programs.