What was going on when I was born?

After a spate of healthy earning reports from most of America's big banks, two of the nation's 10 largest bank holding companies reported sharp declines in net income yesterday. The BankAmerica Corporation, the nation's second-largest bank holding company, said earnings in the third quarter dropped 29.1 percent from the same period a year ago. The sharp drop in net income, which took Wall Street analysts by surprise, was attributed by the bank to higher personnel expenses associated with the acquisition of the Seafirst Corporation, which it took over last July, weak loan growth and the effect of problem loans. Seafirst was a casualty of the failure of the Penn Square Bank of Oklahoma City, from which it had purchased $400 million in energy loans.

Washington will not allow Syria, ''aided and abetted by 7,000 Soviet advisers and technicians,'' to destroy the chances for stability in Lebanon, President Reagan said. In a nationally-televised news conference from the White House, Mr. Reagan also said he did not believe that the ''free world would stand by and allow the Straits of Hormuz'' to be closed to oil traffic by Iran. The President declined to say what actions might be taken if the Iranians closed the key waterway at the mouth of the Persian Gulf. (Page A1, Column 6.) Four marines were wounded slightly by the explosion of a car bomb as a convoy of four American military vehicles moved along a road near Palestinian refugee camps in Beirut's southern suburbs. (A13:1-3.)

After months of negotiations and squabbling, Governor Cuomo and Mayor Koch announced agreement yesterday on the last major issue in the $1 billion redevelopment of the Times Square area. At a news conference, they said they had agreed on a consortium to develop a 2.4-million-square-foot wholesale merchandise mart at the southeast corner of 42d Street and Eighth Avenue. The agreement came two months after New York City said it would pull out of the joint project with the state's Urban Development Corporation because of a dispute over which of two teams of private developers would get the project. 'Firm' Agreement Reached Under the agreement, a consortium involving both development teams was formed and will begin negotiations with the Times Square Redevelopment Corporation, the public agency in charge of the project.

Six years ago, Mary Rodriguez was so intimidated at being seen running that she had her husband drive her to a park near their home in Rego Park, Queens, and wait while she completed her modest training runs. ''I got into running through a New York Road Runners Club exercise class on a Saturday morning,'' Mrs. Rodriguez recalled. ''I couldn't even run a city block. It was embarrassing. That first week, the exercise teacher said to me, 'Don't give up, you can't expect to undo 35 years of inactivity in one week.' ''

Companies A.T.& T. plans to charge off $5.2 billion against 1983 earnings as part of its transformation from protected monopoly to competitive enterprise. It would be the largest such charge-off in corporate history. The move could make A.T.& .T. a more attractive investment, experts said, because it would be earning the same amount of money on what will appear to be a smaller asset base. (Page A1.) The F.C.C. said tariff charges proposed by A.T.& T. could lead to significant increases in long-distance rates for business. (D5.) Two of the nation's 10 largest banks reported sharp declines in earnings after a number of others had posted healthy gains. BankA merica's third-quarter earnings declined 29.1 percent, while those of Continental Illinois fell 38.9 percent. (D1.) American Airlines and Piedmont Aviation reported higher earnings. (D6.) Time Inc.'s net income fell 13.9 percent. (D6.) Earnings rose 34.2 percent for RCA and 71.6 percent for Weyerhaeuser. (D6.)

James D. Berry, the chairman of the Republicbank Corporation, remembers only too well that day early last year. Republic, then the third-largest bank holding company in Texas, by assets, was not getting its share of the boom in energy lending that was still sweeping the nation's oil-producing heartland. Mr. Berry recalled that at a meeting with his senior loan officers ''I told them we were losing market share and wanted to know what we could do about it.'' But the lending officers ''looked at me like a tree full of owls'' and convinced him not to alter the bank's relatively conservative policy.

Secretary of State George P. Shultz appealed to the House of Representatives today to continue United States aid to rebels fighting the Nicaraguan Government. The Secretary warned that a cutoff of assistance ''would virtually destroy'' prospects for getting the Nicaraguan Government to stop assisting leftist guerrillas in El Salvador. At his news conference tonight, President Reagan defended covert backing by the United States for Nicaraguan rebels. But he refused to be drawn into the Central Intelligence Agency's involvement in planning or helping mount recent sabotage attacks in Nicaragua.

The Senate gave final Congressional approval today to a bill to create a Federal holiday to honor the Rev. Dr. Martin Luther King Jr., and President Reagan said he would sign it because of its symbolic importance. But the President said he did not fault the sincerity of those who wanted to obtain access to sealed files of the Federal Bureau of Investigation on Dr. King because of questions over whether he had associated with Communists. And he declined to give any opinion on whether he believed such allegations were accurate. Mr. Reagan made his comments at his 20th televised news conference, shortly after the Senate, voting 78 to 22, gave final passage to a bill making a Monday near Dr. King's birthday the 10th Federal holiday. (Page B9.)

President Reagan said tonight that the United States would not allow Syria, ''aided and abetted by 7,000 Soviet advisers and technicians,'' to destroy the chances for stability in Lebanon. He said the Syrians were seeking to do this by their efforts at ''foot-dragging'' in the search for peace. In a televised news conference in the White House, Mr. Reagan also said he did not believe that the ''free world would stand by and allow the Strait of Hormuz,'' the exit from the Persian Gulf, to be closed to oil traffic by Iran. Iran Threatened to Close Strait The Iranians have threatened to close the strait if the Iraqis, with whom they have been at war since September 1980, use French Super Etendard bombers to launch Exocet missiles against Iranian oil targets. Mr. Reagan refused to go into details on what military actions might be taken in case Iran closed the strait.

The House Ways and Means Committee today completed the drafting of a bill to tighten a broad array of tax-law provisions, including those governing the issuing of tax-exempt industrial development bonds. The measure would produce $10 billion in additional revenue over the next three years. The bill, described as a bipartisan effort by the committee's chairman, Dan Rostenkowski, an Illinois Democrat, and Barber B. Conable Jr. of upstate New York, the committee's senior Republican, is likely to reach the House floor next week. At that time, it is expected that various Democratic efforts will be made to amend it to raise as much as $63 billion more to meet the $73 billion target set by Congress.

HE has a longstanding relationship with the 1892 building. Not only was John Paci Jr. born there in 1946 but he has been doing repairs there since he was 14 years old. The five-floor tenement structure on the Upper East Side has been, since 1927, the property of Luigia Paci, his 86-year-old grandmother. About seven years ago, when one of the 20 apartments in the rent-regulated building was vacated and in terrible condition, Mr. Paci, a public-school teacher when he is not doing repairs, started knocking a wall down to patch it up. ''The whole thing gave way,'' he recalled. ''I was so disgusted I walked out and didn't come back for two months.''

A headline on the Broadway column in Weekend on Friday misidentified the producers of the musical ''Peg.'' It will be produced by Zev Bufman with Irving and Margie Cowan.