Philanthropic giving by organized religion in the United States exceeds that of all the nation's corporations and secular foundations combined and has shifted from "redeeming souls" toward changing society, in part to compensate for cuts in government support for the needy, according to the most comprehensive study ever of the subject.

The 144-page report, "The Philanthropy of Organized Religion," released today by the Council on Foundations, marveled at the creativity and increasing sophistication of religious giving.

Contrary to a common stereotype, it said, "religious organizations are indeed donors, not just recipients," and nearly half are operating in ways similar to foundations, giving grants or loans or making investments, "doing much of it in ways that are blazing new trails for the philanthropic enterprise."

Giving by religious organizations at the national and regional levels probably totaled at least $7.5 billion in 1983, for example; and that total doesn't include an estimated $1 billion given at the congregational level and possibly additional billions that eluded the survey, the report said.

This compares with $3.1 billion given by corporations and their foundations, and $3.46 billion given by other secular foundations.

The study contrasted the public fanfare associated with "the Rockefellers and the Fords, the Carnegies and the Exxons" with the "quiet army" of religious givers, whose efforts have gone remarkably unsung.

Through religious giving, "every conceivable need in society is being addressed, from soup kitchens in urban areas to making films about social justice, from building wells in the Sudan to emergency food aid in Ethiopia," said James A. Jo- seph, president of the Council on Foundations, a national organization of 950 such groups and grant-makers.

The trend toward grant-making, he said, is particularly encouraging, because it shows there is an "increasing focus on bringing to the charitable spirit a new professionalism . . . . Giving based on the charitable feelings of the giver [the more traditional practice] is nice. But the use of these more sophisticated management techniques maximizes the impact of the philanthropic dollar."

He cited as an example a program run by the Catholic Sisters of Mercy, who sold their headquarters property in Potomac and used the money to form a foundation called Mercy Action.

One hoped-for result of the survey is "more collaboration among all givers," Joseph said.

While religious organizations are "still among the first to spring to the aid of the distressed," the report said, many groups "are alive with activities designed not only to put the finger in the dike, but to turn the waters around," including low-cost housing loans and free dental care, community-based organizing and making films on toxic-waste problems.

"Almost as many religious groups are working for justice, human rights and advocacy issues as are offering direct aid to the hungry and stateless," it said.

Among those engaged in advocacy, peace is an "overriding concern," the report said, with social justice and women's issues top runners-up.

A trend toward social action, as opposed to saving souls only, was apparent even among evangelical organizations such as those of Southern Baptists, whose primary activity is "church planting," the report noted.

More than half the groups are active internationally, particularly in Latin America, the Caribbean and Africa. Roman Catholic groups are focused more intensely in Latin America, with its high Catholic population, while Jewish groups favored the Middle East and non- denominational groups favored Africa.

One-third of the groups surveyed said they funded projects where there was a need, without regard to the race of those involved. While they tended to favor populations that reflected the makeup of their own membership, most funded two or three racial groups at once.

Among the examples of activities cited in the United States were the installation of computers in a school, not only for students but also for job training for the community's low-income population; seed money to train women in the construction industry; aid to a center to assist workers hurt by business or plant closings; aid for construction and sale of low-cost solar-heated housing for poor rural people; and funding for a rape-counseling center.

International programs included special education for deaf children in 20 African countries; a cocoa-production marketing initiative in Haiti, resulting in a 50 percent increase in return to farmers; "barefoot-doctors training" for third-world nationals to become para-professionals; eight orphanages in India and funding a film on the exploitation of Third World women.

This study, considered preliminary to further research, did not seek information on the tangled sources of religious income. But it found indications that "religious groups engaged in large-scale efforts with refugee aid, hunger overseas, foster care, adoption and disaster relief are likely to receive considerable flow-through funds from government contracts."

The respondents were asked not to include funding of their own church facilities and activities.