President Carter has left even many of his administration's own officials wondering how literally to take the soaring rhetoric of his foreign policy speech at Notre Dame University.

Was it a landmark in the Carter administration's reach to recapture the high ground of "moral authority" in the world?

Or was the speech at South Bend on Sunday another commencement address, reverting in campaign style to scoring off Nixon-Ford-Kissinger once again, as it did, for "secret deals" and "policy by manipulation"?

Even some insiders were debating that yesterday as they studied the President's remarks. But others expressed certainly that the Carter speech was destined for long remembrance as the most meaningful exposition so far of his evolving foreign policy.

It clearly was the President's intention to have the address serve as a major guidepost for the future, associates say. However, even enthusiasts cannot foretell precisely what the speech foreshadows in specific policies, for it was cast, as one admirer noted, in "rather Delphic terms."

One result of developing administration policy, as Vice President Mondale also said on Sunday in a narrower context in describing the administration's formal challenge to South Africa's apartheid, is that it makes "most Americans feel very good . . ."

The President, in concluding his own address at South Bend, made a similar and broader claim. By basing U.S. policy "on an historical vision of America's role" that is "rooted in our moral values" and "designed to serve mankind," Carter said, his administration is producing "a new American foreign policy" that "I hoped will make you proud to be American."

Henry A. Kissinger used to dismiss this kind of language in private, and sometimes even in public, as "moralizings" or "sermonizing." In the end, the charge that Kissinger scorned morality became his heaviest burden.

What President Carter was projecting on Sunday beyond the recaptured moral vision is equally venturesome in theme although much less discernible in specifies.

" . . . We are now free," he said, "of that inordinate fear of communism which once led us to embrace any dictator who joined us in our fear." This helps to explain his administration's moves to normalize relations with Cuba and Vietnam, but the counterpart, the breaking of embrace with dictatorial regimes, is thus far less evident.

Carter also reiterated, "I believe in detente with the Soviet Union." But repeating a phrase first used by national security adviser Zbigniew Brzeinski, Carter said that relationship "must be both comprehensive and reciprocal," both with the Soviet Union and China. And although the Carter administration formally has renounced the Nixon-Kissinger concept of "linkage" in U.S. Soviet relations, the President nevertheless said: "We cannot have accommodation in one part of the world and the aggravation of conflicts in another."

Here Carter - much like Kissinger - condemned Soviet "use of a client state's military force - as with the Cuban intervention in Angola," to "impose its own social system upon another" nation.

Carter said, "The unifying threat of conflict with the Soviet Union has become less intensive, even though the competition has become more extensive.

At the same time, historical trend he said, have weakened the West's post World War II system for competing with the Soviet Union - belief in the importance of an almost exclusive alliance among non-Communist nations on both sides of the Atlantic."

It would be difficult, however, to distinguish many of the Carter goals from his predecessors such as reducing the chasm between the world's rich and poor or removing "the threat of nuclear war, racial hatred, the arms race enviromental damage, hunger and disease." What Carter added was a more zealous sense of compassion, a more intense pledge of commitment to "justice, equity and human rights."

Carter policy seeks a broader world order, in which the United States "will cooperate more closely with the newly influential countries in Latin America, Africa and Asia."

By making the first touchstone of his administration's foreign policy, a "basic commitment to promote the cause of human rights," Carter has reiterated that he will not back off from that controversial international objective.

"I understand fully." he said, "the limits of moral suasion. I have no illusion that changes will come easily or soon. But I also believe that it is a mistake to undervalue the power of words and of the ideas that words embody."

What will count in the long run, however, he surely recognizes, is not merely if his policy only makes Americans "feel very good" but whether it is workable.