"When the tears are over, when the anger has subsided, we must continue the negotiations out of which we further pray that peace will emerge."

Washington's Episcopal Bishop John T. Walker, addressing a memorial service attended by President and Mrs. Reagan yesterday at the Washington Cathedral, echoed the mixed reactions of many church leaders to the shooting down of a Korean airliner last week by the Soviet Union.

Walker and others who have advocated nuclear negotiations with the Soviets minced no words over the Russian action. The Episcopal churchman called it a "senseless atrocity inflicted upon us all by . . . an outlaw in the family of nations . . . . There is no way to justify the destruction of helpless, innocent people." But "when the demonstrations have ended," he said, "the hard work of negotiation" for world peace must resume.

Archbishop John R. Roach of St. Paul/Minneapolis, president of the nation's Roman Catholic hierarchy, called the attack "an act of murder," adding, "The international community cannot tolerate such actions."

The "tragic episode," Roach said, highlights "the danger and fragility of international relations today." But he urged, "despite this massive and evil tragedy, U.S.-Soviet negotiations on nuclear arms limitations must continue."

National Council of Churches general secretary Claire Randall and United Methodist Bishop James Armstrong, who is NCC president, called the shooting down of the plane "a violation of international agreements and moral standards." In a message to the Korean Council of Churches, the U.S. Protestant leaders supported the call for "an international inquiry into this serious incident."

The NCC leaders also sent identical telegrams to Moscow to Metropolitan Filaret of the Russian Orthodox Church and Alexei Bichkov of the Union of Evangelical Christian Baptists in the Soviet Union saying: "Profoundly distressed and saddened by Soviet military action against Korean civilian airliner which claimed 269 lives on Sept. 1. This tragedy demonstrates anew the disastrous consequences for world peace, disarmament and improved international relations of the reliance upon and use of armed force . . . "

In New York, a spokesman for the World Council of Churches, whose membership includes both Russian and Korean churches, said a statement had been prepared by that organization but had "been held back."

In a message to priests urging prayers for victims of the crash and their families, Washington Archbishop James A. Hickey said the Soviet action "merits universal and unequivocal condemnation." Hickey joined others in the call for further investigation. "The international community should seek effective measures both to punish this barbaric act and to prevent its recurrence," he said.

The Justice and Peace Commission of the Baltimore Catholic archdiocese has sent a letter to Ambassador Anatoly F. Dobrynin expressing "profound shock" and calling on the Soviets for an explanation. But the commission also stressed the need for cooperation "in matters of global security."

The Council of Korean Churches in the Greater Washington area expressed appreciation for President Reagan's "prompt action and initiative."