Following Moshe Dayan's resignation, Prime Minister Menachem Begin's coalition faced a new threat tonight as Agriculture Minister Ariel Sharon vowed to quit the Cabinet if the controversial Elon Moreh settlement in the West Bank is dismantled.

A crisis atmosphere surrounded the beleaguered prime minister as he mustered his parliamentary forces to beat back easily five separate no-confidence motions to bring down the government today.

Dayan, in his first press conference since resigning Sunday, tonight contradicted Begin's assertions that their disagreement involved procedural matters. Dayan said substantive differences about the ultimate status of occupied Arab territories was the issue.

He "would not prefer Israeli sovereignty over the 1.25 million Arabs" in the occupied West Bank and Gaza Strip "if there is a better way," Dayan said.

"The question is not only how we technically carry out the negotiations with the Egytians on [Palestinian] autonomy, but how we visualize the final status, the permanent status of Judea, Samaria and the Gaza Strip. Will it become part of the soverignity of Israel or will it not? Is this what we are after or not?"

Today, Dayan voted with the Begin government to defeat no-confidence motions, but he would not commit himself on future votes. While the motions were defeated by a decisive majority of the Likud coalition, Sharon's threat to quit presented Begin with a seemingly insoluble dilemma.

The prime minister can either defy a court decree ordering that Elon Moreh be removed within 30 days or he can dismantle the controversial settlement on the West Bank and incur the wrath of the conservative factions of his fragile coalition.

Sources said that Sharon notified Begin that he had told the Elon Moreh settlers, encamped near Nablus on the site the High Court said was improperly expropriated wfrom Arabs, that the only reason he remained agriculture minister is to support the settlement movement.

In the Knesset (parliament), Labor opposition leader Shimon Perez blamed the Begin government for the Elon Moreh problem and vowed that the Labor Party would not tolerate any government "tricks" to preserve the settlement.

In his press conference, Dayan said he expects the government to make some "clear decisions" about its settlement policy as a result of the Elon Moreh court case. Apart from major economic problems, Dayan predicted more political tribulations for the Begin government mainly stemming from the intention of the ultranationalist Gush Emunim group to build more Jewish settlements on the West Bank.

While it was widely known that Dayan had substantive differences with Begin on West Bank policy, today was the closest the former foreign minister came to pinpointing those differences, other than to say there were difference of technique and on how the Palestinian autonomy negotiations should be conducted.

"Would we allow any partition when we negotiate with Jordan after five years, or should we not give one inch? Where to be flexible and where to insist and not give in anything?. . . The relations between the arabs living there and Israelis, and the question of sovereignty and all that, my concept is not identical to the concept of the Likud and the National Religious Parties," Dayan said.

While Dayan made it clear what he would not accept a Palestinian state and closed borders as a permanent status of the West Bank his specific vision for the occupied territory remained as elusive as ever except for amorphous hints at a Palestinian federation with Jordan.

But his explanation, given in a farreaching and sometimes rambling news conference that lasted more than 2 1/2 hours, contradicted assertions by Begin and his top aides that Dayan quit principally over his isolation from the autonomy talks and because his views of bargaining techniques differed from the government's.

Referring to a set of Cabinet-approved autonomy negotiating principles, which include a claim of Israeli sovereignty over the West Bank and Gaza, Dayan said, "In some of them, at least one, I did not agree and I voted against."

The principles, adopted last spring also demanded Israeli control of West Bank water resources, continued settlement, application of Israeli law to settlers and the use of Israeli law enforcement units to protect settlers.

Dayan did not make clear why he did not quit when the principles were adopted. An aide to Dayan said later, "There was always hope for change."

Dayan said he would remain in the Knesset, but he said he has no intention of forming a new party. He said he plans to write a book, travel and give lectures.

Dayan sidestepped questions about whether he believes his resignation coupled with yesterday's landmark High Court decision against the government-sponsored Elon Moreh settlement, would ultimately cause the Likud coalition to collapse.

"I'm not an expert on when and why a new election will take place. I'm not involved, and I don't even count the numbers or supporters of the Likud," he said. (The Likud majority has dropped through political attrition from 77 to 65 Knesset members).

In response to questions, he said he was ot leaving the government because of the Likud coalition's weakened condition, which has been exacerbated by political and economic problems.

Dayan, who has been regarded as a moderating influence on the Cabinet's foreign policy, doubted whether the government will take a harder line now, particularly on settlements, in light of the Elon Moreh ruling. I'm sure they will do their best to reach an agreement," he said.

In a poignant footnote to his three decades of service to the Jewish state both as an Army officer and politician, Dayan, who recently had a maligancy removed from his intestines, was asked about a recurrent dream he wrote about during his illness.

The dream was that while climbing a steep hill to view a pagoda during an Asian tour, he overcame his fatigue because he felt pushed up the hill by a mysterious force. But, at the top of the hill, he realized, was the cemetery of his native Galilee kibbutz, Nahalal.

When asked why he wrote about his dream, Dayan explained he had been under intense physical and emotional strain before his operation. He quoted from a poem the observation that dreams about death can come true.

Then, characteristically, Dayan noted that another verse of the same poem said that dreams about death do not necessarily have any meaning.