Sen. Frank Church (D-Idaho), the new chairman of the Senate Foreign Relations Committee, last night sharply rebuked the Carter administration for abandoning "the path of Camp David" and making a mess of its own Middle East peace policy.

Church urged the administration to put dirct pressure on Saudi Arabia to support the original results of the Camp David summit, including the threat of reconsidering the sale of advanced F15 warplanes to the Saudis.

Church made his first comprehensive criticism of administration foreign policy as chairman of the Senate committee in a speech to the Antidefamation League of B'nai B'rith in Palm Beach, Fla. Church released the text of his speech in Washington.

Before leaving Washington yesterday, Church said that Saudi Arabia now is the crucial factor in the stalled search for peace in the Middle East. "They can make or break the peace," Church said.

In his speech, Church said he thought that "now is precisely the time to inform the Saudis that a 'special relationship' cannot be a one-way street.... They cannot coune on our unequivocal support... without a demonstration on their part that they are responsive to out fundamental concern, the successful conclusion of an Israeli-Egyptian peace treaty."

Church's speech comes at a time when the Carter administration is deciding how to salvage the Camp David accords.One option under discussion is to bring Egyptian President Anwar Sadat and Israeli Prime Minister Menachem Begin back to Camp David for another round of direct talks.

This is alos a period of uncertain relations between the United States and Saudi Arabia, which is apparently planning to curtail its oil production despite the loss of Iranian oil to the world market. Saudi Arabia also may be toying with the establishment of diplomatic relations with the Soviet Union.

Church blamed the administration for fouling its own nest in the Middle East by implicitly abandoning the clever stategy that made Camp David possible and choosing a pro-Arab position that was bound to alienate the Israelis and to make them intransigent.

The original strategy, Church said, recognized four "tactical priorities":

An Egyptian-Israeli peace treaty should be quickly completed before opposition to it in the Arab world could coalesce.

The United States, Egypt and Israel would not let Jordanian or Palestinian reluctance slow down their movement toward an Egyptian-Israeli treaty.

The United States would try to neuralize Saudi opposition to the proposed peace treaty.

The United States and its allies "would invest in peace" by providing material rewards to Egypt and Israel for reaching a peace agreement.

All four of these went awry, Church contended, and he blamed that on U.S. behavior. Specifically, he criticized the Mideast mission of Assistant Secretary of State Harold Saunders, who infuriated the Israelis last year by appearing to go well beyond the Camp David accords in assuring King Hussein of Jordan and the Palestinians that the United States was sympathetic to their interpretrations of several disputed issues.

The primary objective of Saunders' mission was to convey answers to King Hussin's 14 questions about the Camp David accords. Church said yesterday that the United States should have told Hussein that he could only get answers to those questions by joining the formal peace process.

Instead, Church said, Saunders' answers to Hussein and his later remarks to Palestinians created the impression that the United States interpreted the Camp David accords in an essentially pro-Arab, pro-Palestinian way. But this was not enough to win over Hussein. It also put Sadat "in the impossible position" of appearing to accept ambiguous formulas at Camp David when the United States was ready to go substantially farther -- at least judging by Saunders' comments.

Then, Church charged, "the authorities in Saudi Arabia concluded that the hard-line position of King Hussein paid off better than the softer line of Sadat," and the Saudis proceeded to endorse the hard line at the Arab summit in Baghdad.

Sadat, Church said, "responding to the perception that he had settled for less than he should have, and now under increasing Saudi pressure, made new demands." This, Church said, led to the present impasse.