Vice President Walter Mondale swore in Joseph D. Duffey as the new chairman of the National Endowment for the Humanities yesterday with a commitment to give "cultural issues in the adminstration the high level of priority they deserve."

Also joining the Vice President in the unusual ceremony which lasted close to and hour were first Lady Rosalynn Carter and Joan Mondale who is the Vice President's wife as well as a major figure in the cultural policy of the Carter Administration. In addition there were speeches from four important figues in the broadened range of the intellectual constituacy Duffy has declared he will serve.

Formerly assistant secretary of state of educational and cultural affairs and the head of President Carter's Washington campaign office. Duffy was asked by the President to take the job in the summer but his formal assumption of it was delayed by reorganization of his former office.

Because such swearings in are usually pro-forma exrcises performed by lower-level dignitaries yesterday's event - before a packed house in the auditorium at the Executive Office Building - was a symbolic gesture meant in part to underscore administration allegiance to cultural affairs. That bond has been questioned in recent weeks by critics who see President Carter by his appointments as "Politicizing" the Humanities Endowment and its sister agency the Arts Endowment.

Those who say that politics and culture do not mix," said the Vice President have missed an important point about both disciplines. No serious student of these issues has ever suggested that esthetic or academic [WORD ILLEGIBLE]120:should be decided by politicans or bureaucrats.

Our social and political system has always demanded - and provided - a [WORD ILLEGIBLE]120:private cultural system. And is the role of the federal government through our two endowments strength that private system without imposing any ideology upon it other than openness. This delicate role implies a commitment to two principles: quality and access."

The Vice President also announced that "this fall we will undertake a review of all federal cultural programs in which the two endowments will have a major role."

The Vice President's remarks seemed directed toward administration critics, including acting National Arts Endowment chairman Michael Straight, who have said that the appointment of Duffey, who is 45 and a man with extensive scholarly credentials, and the apparently imminent nomination of Livingston Biddle to the arts chairmanship could undercut the independence of the agencies from political influences. Straight also has charged that the White House has failed to appoint a cultural adviser to the President, so that Joan Mondale "can be given a free hand in this area."

The swearing-in ceremony also included another symbolic aspect. Instead of making a speech himself, Duffey asked four persons to speak briefly on the dicerse conceptions of the "humanities." They were M. Carl Holman, head, of the National Urban Coalition and a poet; George Alexander Heard, Vanderbilt University's chancellor and chairman of the Ford Foundation's board; Isabel Charles, a dean at Notre Dame, and Robert M. Coles, the psychiatrist, educator and author of the Pulitzer-prize-winning "Children of Crisis."

Coles' eloquent call for the endowment to "strive to do justice to and to document the richness, the diversity of cultural life in a nation whose people are not, many of them, afraid to say what is on their minds as well as sing or draw or paint or write what is on their minds" seemed particularly to reflect Duffey's views of the endowment's future. Duffey has called for a broadening of the endowment's public impact, with the support of a President who has attacked its "elitist image."

Following the ceremony was a party at the Corcorn Gallery that was anything but elitist in tone, what with popcorn, apples, beer, white wine and music by Hickory Wing, a progressive folk orchestra.

Among the guests was Straight himself, who merely observed, "This is Joe's day. I don't want to go on talking."

Among the guests, it was difficult to find much concern on the "politicizing" issue. Chancellor Heard said that he thinks there are "sufficient constraints" built into the system. Coles said he regards the issue as "a red herring." Librarian of Congress Daniel J. Boorstin said, "I haven't seen evidence of politicization myself."

Asked later how she thought the event had gone, Duffey's wife, Anne Wexler, deputy undersecretary of commerce for regional affairs and economic cooperation, said she was pleased by "the emphasis on the future . . .on taking the humanities beyond the boundaries of monographs."

Duffey himself said he hoped the ceremony helped to dispel the myth "that there is a small group in Washington and New York who dominate things. That is a dangerous tendency and should be fought, symbolically and otherwise."