Richard M. Nixon became the 37th President of the United States yesterday with a “sacred commitment” to devote himself and his office to the cause of peace.

The grocer’s son from the small town of Whittler, Calif., the only man in this century to be defeated for the Presidency and then come back to win, completed the oath of office at 12:16 p.m. Less than two weeks ago he celebrated his 56th birthday.

In a solemn and restrained Inaugural Address, devoid of slogans, orator’s gestures or specific proposals, Mr. Nixon promised to listen as well as to lead in the quest for national and international reconciliation.

He called upon Americans to “lower our voices” and to shun inflated and angry rhetoric.

“We cannot learn from one another until we stop shouting at one another, until we speak quietly enough so that our words can be heard as well as our voices,” he declared.

The physical security accorded the new President on his first day in office was the most elaborate in memory, including more than 3000 District police, 5000 regular troops and 1000 National Guardsmen deployed at the Capitol, along the parade route and throughout the city.

The disorderly demonstrators numbered about a thousand among the many thousands along the parade route.

According to District police, a total of at least 81 persons were arrested in the disorders. Twelve persons were injured, including one policeman.

For the most part, however, Mr. Nixon was greeted with good will and good wishes expressed with much the same spirit of restraint that characterized his Inaugural Address. There seemed to be a sense on all sides that the Nation’s problems are too deep and the difficulties too severe for either exultation or partisanship.

The Democratic Party’s power was forged in the depression when, Mr. Nixon noted, the Nation’s deepest troubles were described by President Franklin D. Roosevelt as concerning “thank God, only material things.”

“Our crisis today is the reverse,” Mr. Nixon declared to the crowd of 65,000 gathered at the Capitol under leaden, windless skies.

“We have found ourselves rich in goods but ragged in spirit; reaching with magnificent precision for the moon but falling into raucous discord here on earth.”

“We are caught in a war, wanting peace. We are torn by division, wanting unity. We see around us empty lives, wanting fulfillment. We see tasks that need doing, waiting for hands to do them.

“To a crisis of the spirit,” he declared, “we need an answer of the spirit.”

While promising to “press urgently forward” in pursuit of the governmental social goals which have been celebrated in his predecessor’s Great Society, Nixon urged the Nation to “look within ourselves” for the solutions to the greater, non-material, problems.

The trappings of spiritual power were also much in evidence. Mr. Nixon began his activities at an Inaugural Prayer Service at the Department of State with prayers or speeches by five clergymen. On the Inaugural platform, he placed his left hand on two old family Bibles as he swore to the oath of office. Five different clergymen, including the Rev. Dr. Billy Graham, rendered prayers for the Nation and its new leaders during the Inaugural ceremony.

At the luncheon for the Nixon and Agnew families, Congressional leaders and Inaugural participants immediately after the ceremony, Nixon said that “the five invocations given today were all prayed to the same God, Who is in this room, and each of those invocations will read well in history.” Besides Graham, the prayers were by an African Methodist Episcopal minister, a rabbi, a Greek Orthodox Archbishop and a Roman Catholic bishop. A Quaker leader from California-representing the faith into which Nixon was born-gave the benediction at the earlier prayer service.

Just before the luncheon, the new President signed his first official papers, including the formal nominations of the 12 members of his cabinet. All of the cabinet choices were quickly confirmed by the Senate except for Secretary of the Interior-designate Walter J. Hickel, his only controversial selection. Confirmation of Hickel is expected soon, perhaps today.

Unlike the Republican assumption of office from the Democrats in 1953 and some other presidential transfers of power in decades past, the relationship between the outgoing and the incoming leaders yesterday appeared to be amicable and, at times, even cordial. At the White House before the ceremony, Mr. Johnson greeted Mr. Nixon with a warm handshake and Mrs. Nixon with a kiss.

On the ride to the Capitol, the two men appeared to be in animated conversation, with Mr. Nixon gesturing now and then with his hands to make a point. The two men had taken the same Pennsylvania Avenue ride together eight years before, when Mr. Nixon was a departing Vice President who had failed in his try for promotion, and Mr. Johnson his successor in what once had been called “the most insignificant office” in the world.

At the Capitol itself, there was but a single passage of implied criticism by Mr. Nixon of his predecessor, despite the Republican’s history of in the 1950s as a fierce partisan and the “throw the failures out” tenor of his 1968 campaign. In arguing that the Government and the people must proceed in harmony in tackling national problems, the new President said - in an apparent reference to Mr. Johnson’s repudiation by public opinion - that “the lesson of past agony is that without the people we can do nothing with the people we can do everything.”

The statement met with applause from the gloved hands of the Republicans who had come to see the transfer of power in the chill of temperatures in the 30s. Mr. Nixon was interrupted eight other times by ripples of applause and the stomping of frigid feet - but none of it enthusiastic or vociferous.

It was not that kind of situation, or that kind of speech. The Inaugural platform was flanked on either side by members of the two houses of Congress, both controlled by the Democratic Party. In front, just ahead of the lectern, was a screen of bullet-proof glass, a reminder of the assassinations which so suddenly had altered the political fortunes of the leaders present.

In attempting to win confidence and support and to firmly establish his leadership, Mr. Nixon shunned all of the crowd-pleasing punch lines from his fall campaign, casting his call to the Nation in spare and general prose. Usually, he memorizes his speeches and embellishes them with gestures. Yesterday he read his speech, changing hardly a word from the prepared text, his arms virtually still.

“We shall only promise what we can produce,” he said, and those promises were general in nature if lofty in purpose.

One was reconciliation of the races - “black and white together, as one nation, not two.” After an era in which the passage of laws was of chief importance, Mr. Nixon said that the job is now to give life to what is law.

Another job is peace. “I have taken an oath today in the presence of God and my countrymen,” Mr. Nixon declared. “To that oath, I add this sacred commitment: I shall consecrate my office, my energies and all the wisdom I can summon, to the cause of peace among nations.”

Mr. Nixon made no specific reference to the Vietnam war, which he is pledged to end on honorable terms. He has scheduled the first meeting of his National Security Council for 2 p.m. today, however, and will meet with Gen. Earle Wheeler, Chairman of the Join Chiefs of Staff, at 3:30 p.m.

Mr. Nixon made no reference to the announcement in Moscow of renewed Soviet interest in talks aimed at curbing strategic nuclear arms. He did propose to “cooperate to reduce the burden or arms” but declared in the next sentence that “we will be as strong as we need to be for as long as we need to be.”

The honor of being peacemaker to the world, he said at another point, is “our summons to greatness” as a nation.

“For the first time, because the peoples of the world are afraid of war,” he asserted, “the times are on the side of peace.”

In the late afternoon, Mr. Nixon reviewed the Inaugural Parade from the stand at the White House, shaking hands with people in the street at the end before entering the Executive mansion to prepare for visits to Inaugural balls. Rain, which had been threatening most of the day, began falling about 6 p.m.

Last night the Nixons and their daughters and son-in-law David Eisenhower toured the six inaugural balls held in their honor. Before they left the White House they entertained 150 relatives and friends at a private reception in the State Dining Room. The refreshments included hot and cold hors d’oeuvres and coffee, but no alcoholic beverages.