Jerusalem — Prime Minister Menachem Begin's political career is ending in the same style in which he led it - with high drama and unexpected moves. After holding the nation in suspense for 48 hours while Cabinet ministers and colleagues pleaded with him to reconsider his declared intention to resign, the weary yet still immensely popular leader agreed to hold back his formal resignation for a few more days. This will give his fragmented coalition time to resolve its internal struggle over his successor.
Mr. Begin's spokesman said it was ''very likely'' that the premier would leave political life.
But the balance sheet on the six years of Israel's ''Begin era'' is already being toted up and it shows a highly contradictory record of achievement and disappointment that leave Israel with a pile of unresolved problems:
* Prime Minister Begin signed Israel's first peace treaty with an Arab neighbor, Egypt, but Israeli-Egyptian relations have progressively chilled over continued occupation of the Palestinian-populated West Bank and Gaza Strip and the invasion of Lebanon.
* Under Begin the infrastructure of Israel's archenemy, the Palestine Liberation Organization (PLO), was destroyed during the invasion of Lebanon, but in the process Israeli troops became bogged down in that country.
* The Israeli leader virtually revolutionized Israel's political establishment, bringing to power for the first time the have-not Oriental Jewish community, but he leaves Israel bitterly divided on political and social issues. Israel is also facing a major economic crisis, which will hit hardest at the have-nots.
Begin, wan and pale, leaves office a far different figure than the feisty, self-confident leader of his heyday who would publicly roast foreign political leaders who displeased him and could whip a crowd into a frenzy with his rhetoric.
His progressive loss of control over his colleagues in government was cruelly illustrated by the disorganization of recent government efforts aimed at resolving Israel's economic crisis. During that time, one minister harshly stated that he felt Israel had become ''a ship without a captain.''
Begin's decline is widely attributed to the passing 10 months ago of his beloved wife of 43 years and to his disappointment in the results of the Lebanon war, the economy, and the squabbling of Cabinet ministers. But his decline is equally connected, many observers here believe, with his style of leadership and his goals in office, which ultimately divorced him from key political realities.
Born in Poland, Begin lost both parents in the Nazi Holocaust, was imprisoned during World War II in a Siberian labor camp, and led the violent Etzel Jewish underground in the 1940s against the British after reaching Palestine.
From his youth he supported the maximalist Zionist position, which sought Jewish control of the lands extending from the Mediterranean across the Jordan River to the borders of Iraq.
After Israel's independence, he spent nearly three decades as the key parliamentary opposition leader - maintaining a simple, almost austere life style - until the political upset that brought him to power in May 1977.
Some say it was the legacy of years out of power that contributed to his very noticeable and much-commented-on lack of interest in the day-to-day working of government. Instead, says Jerusalem Post columnist Yosef Goell, ''He had his eyes firmly fixed, not so much on the big picture as on the one point which he assumed was the hub around which the big picture rotated: the firm, secure, and irreversible establisment of a Greater Israel (pre-1967 Israel plus the occupied West Bank and Gaza Strip).''
At the heart of the Begin's program was the need to ensure that Israel would never lose the occupied territories which he believed were rightfully Israel's for historic, religious, and security reasons. He was little interested in economic matters and paid scant attention to the deterioration of the Israeli economy under a succession of finance ministers in his two governments.
From the beginning his ministers, who at first included strong men like Foreign Minister Moshe Dayan and Defense Minister Ezer Weizman, quarreled fiercely, but at his peak he would skillfully maneuver them into line. It is a testimony to his former charisma and continued public popularity that the same ministers who have been criticizing him openly have in recent days been imploring him to stay in office.
His greatest achievement, the peace treaty with Egypt, was based on a trade-off: He expected that the return of Sinai to Egypt would ensure that Israel would then be able to retain the remaining occupied Jordanian and Syrian territories.
His desire to ensure Israeli sovereignty over the West Bank also ultimately led him to the invasion of Lebanon in June 1982. Security for Israel's northern settlements - long threatened by rockets fired by Palestinian guerrillas across the Lebanese border - was one goal of the war. But its real aim, as subsequently revealed by Israeli military and political leaders, was to ensure that Israel could keep the Palestinian-populated West Bank and Gaza by destroying the Palestinian leadership structure based in Beirut.
But Begin made what many observers here believe was a critical error when he appointed as defense minister in July 1981 the man who became the architect of the Lebanon war, Ariel Sharon.
Begin, a loner, did not like competition in his Cabinet. His second administration included no strong or well-known figures. He distrusted Mr. Sharon, a flamboyant former general with a reputation for ruthlessness, and kept him from getting the Defense post in 1977 and again in 1980.
But finally Begin, an admirer of General Sharon's military skills, acceded not only to Sharon's joining the government but to his argument that the road to the West Bank lay through Lebanon.
Begin's lack of control over Sharon was already apparent during the war when he admitted publicly that the defense minister informed him of events after they happened. He learned of the Sabra-Shatila massacre of Palestinians in Beirut only from a BBC radio broadcast.
Sharon did destroy the PLO infrastructure, and Israel might have emerged safely from the war had it then withdrawn its troops in return for security arrangements in south Lebanon. But on Sharon's advice, Begin demanded a virtual peace treaty with the Lebanese and made Israeli withdrawal contingent on withdrawal of all Syrian troops from Lebanon.
The result: Syria has refused to pull out its soldiers, leaving the Israeli government boxed into keeping its soldiers in Lebanon or explaining to the Israeli public why the promised goals of the Lebanon invasion were not achieved.
The prime minister's disappointment in Lebanon - and the mounting Israeli casualties there - were a major contribution to his depressed state of mind over this past year. As Lebanon disintegrated, so did Begin's hold on his government. Ministers struggled over the future succession and fought over trimming the budget. At the end, ministers were voting down the few matters of economic policy on which Begin had taken a personal stand.
In fact, Begin did ensure his goal of Israel's de facto control over the West Bank for the foreseeable future. But the price cannot yet be measured, except, perhaps in its indirect contribution of the resignation of the prime minister.