President Carter today stepped into the controversy that has erupted in the wake of U.N. Ambassador Andrew Young's resignation, urging blacks and Jews to resolve their differences and not import world quarrels into American life.

Ending his silence after two weeks of growing tension between the groups, Carter said:

"Black Americans and Jewish Americans have worked side by side for generations in the service of human rights, social justice and the general welfare . . . Both groups have suffered too much pain, too much persecution, too much bigotry to compound that suffering in any way.

"We must seek resolution of differences and we must stand with each other to prevent all these quarrels of the world from being imported into our own national life," he added.

The president made his remarks at a ground-breaking ceremony for a new chapel at Emory University, during a trip that took him to an energy symposium here and a town meeting later in Tampa, Fla., where he predicted a decline in food prices in coming months.

Carter never actually spelled out his view of the nature of the recent differences between American blacks and Jews. But his comments on the dispute came immediately after passages in which he gave strong praise to departing Ambassador Young.

And it was clear that he was referring to the tensions created by the fact that Young resigned under pressure after he met with an official of the Palestine Liberation Organization and Israel officially protested the session.

Carter's decision to speak openly about this politically sensitive controversy came after his domestic policy adviser, Stuart E. Eizenstat, suggested the idea to him in a memo this week. A number of prominent Jewish leaders had been privately telling White House advisers that the president should exert some leadership to calm the simmering crisis.

On Tuesday, Eizenstat wrote a memo to Carter urging that he do just that, and suggesting the Emory University speech as a forum, according to a White House official.

Eizenstat's view was that Carter had told the nation last month that he would be speaking out and exerting leadership on major issues, and this controversy, though politically sensitive, was so potentially explosive that the president had to address it publicly and promptly.

Carter agreed on Wednesday, the official said, and summoned chief speechwriter Hendrick Hertzberg and began drafting the speech.

Emory is a Methodist institution and the chapel ground-breaking took the form of a religious convocation. So it was, Carter aides conceded, that the president's speech was deliberately sermonesque.

The president invoked the Scriptures of Isaiah, the teachings of John and Charles Wesley, the writings of Arnold Toynbee, and the "ethics of the Judeo-Christian tradition." But mostly, his speech was a plea for unity in America, especially between blacks and Jews.

"The motto of our country is 'E Pluribus Unum' -- 'Out of Many, One'" Carter said. He added: "Of course, we are proud of our diversity . . . but we must not permit diversity to degenerate into division. In a time of trial we must not permit the legitimate contest of competing views to become a war of group against group, special interest against special interest, and finally each against all others."

Young had been expected to share the podium with Carter yesterday, but was called back to the United Nations to preside over a meeting of the Security Council, where he is serving this month as president. Two weeks ago, Carter accepted Young's resignation after Secretary of State Cyrus R. Vance told him, according to informed sources, that he felt Young could no longer stay in office. Yesterday, Carter had only high praise for Young.

He noted that Young had gone to the United Nations at a time when developing countries "looked upon the United States with fear and distrust." Carter said that Young's work had helped "millions of poor and oppressed people throughout the world to understand that we support their longings for justice and a better life."

The mention of Young's name brought cheers from the audience of several thousand on this campus in the city Young used to represent in Congress.

Carter used his praise of Young to set up his discussion of tension among blacks and Jews. "As Andy leaves the United Nations," Carter said, "our common task is to look ahead with a sense of caring and concern for the social fabric of our country and for a more peaceful, fair and just world.

" . . . Every American has the right to debate all public issues, including issues of foreign policy. Open debate and the free exchange of ideas are the heart and soul of our political system. But differing political views, when and if they do exist, must not become the occasion for deep and damaging divisions between groups of citizens in our society."

Shifting from the politics of dissension to the morality of sermon, Carter ended his speech by finding hope in a crisis that he said exists today. "Throughout our history, crisis has been the occasion for rethinking, redirection, and resurgence," Carter said. " . . . I pray that from our present material and spiritual crises there may come a new sense of awakening and a new pursuit of more fulfilling ways to live and work together. Let us confess our failures, marshal our inner resources and move on -- upward."

Carter began the day by flying to Atlanta to spend a couple of hours listening to a seminar on energy technology. While there, he also met briefly with the executive committee of the National Conference of Democratic Mayors, which happened to be meeting in Atlanta. They discussed urban problems, and the mayors urged increased funding for the Law Enforcement Assistance Administration, which Congress has cut back substantially.

Before leaving Atlanta, Carter said he had no quarrel with the way Israeli intelligence officials operate in the United States. He made his comment during a brief plane-side interview with a local television reporter before boarding Air Force One. The president was asked if he was bothered by Israeli intelligence operations in the United States. He replied:

"Well, I think there's nothing abnormal about that. All countries have some form of intelligence operations in other countries. And it consists of collections of data, interviews with private citizens, perusal of news media and also some secret devices. But there are boundaries of legitimacy and I think the Israelis honor those boundaries, just as we do."

Carter made his good news comment on food prices at a town meeting that had been billed as a session on energy. Speaking to a cheering and largely enthusiastic audience of about 2,000 in a high school gymnasium, Carter said in response to a question:

"I think I can tell you that the last few weeks, for the first time, retail food prices have begun leveling off -- and the projections are that they'll go down." He said he expected the "moderation" in food prices to begin "shortly," adding: "Food's going to get better."

Carter said that pork and poultry production has been "very high," and that this will "force the price of beef down."

Carter also criticized food industry middlemen for excessive profits. "The people that process and distribute meat are making too much profit," he said. These middlemen have not passed on their savings to the consumers in the form of lower prices, Carter said.