When Prime Minister Menachem Begin signed the peace treaty with Egypt three years ago he declared that ''in Jewish teachings, there is a tradition that the greatest achievement of a human being is to turn his enemy into a friend.'' It will sadden the world that Israel, contrary to that sentiment, once again seems to be doing everything to perpetuate the enmity of its neighbors. Mr. Begin's abrupt annexation of the occupied Golan Heights - without even informing the United States - not only flagrantly violates international law. It can only confirm the fears of Syria and other Arab states that Israel is an expansionist power and that Zionism is dangerous. How can this possibly serve the cause of Israel's long-term security?
To all intents and purposes, it would appear that UN Resolution 242, which has provided the foundation for the Middle East peace process, is no longer viable. Successive Israeli governments have supported that resolution, calling for Israel's withdrawal from land occupied in the 1967 war, including the Golan Heights. The terms of withdrawal are supposed to be negotiated, and in such a way that Israel is left with ''secure and recognized borders.'' The late Israeli foreign minister Moshe Dayan was even prepared to give up the Golan Heights, despite their commanding vantage point and the physical protection they afford Israel.
But with one swift stroke, Mr. Begin and the Knesset have now undermined the chances of a peace agreement with Syria. The unilateral act also puts a cloud over the Camp David peace negotiations for autonomy of the West Bank. It is doubtful that President Mubarak of Egypt will do anything to disrupt the peace accord with Israel inasmuch as he awaits the handing back of the last chunk of Sinai still under Israeli control. But, if the autonomy talks break down, many believe Mr. Begin could move to annex ''Judea and Samaria'' as well.
What should the United States, Israel's friend and partner, do given Mr. Begin's repeated acts of defiance? The Reagan administration cannot but feel frustrated to see US national interests so often undercut. Only recently it concluded an agreement on strategic military cooperation with Israel, yet Israel has now made a move with harmful strategic implications.Washington has critized the Golan grab, but it is clear that mere public denunciations of Israeli actions do little good.
Has the time come for a stronger response? Some Mideast hands suggest the US ought to make clear to Israel that it must bear the consequences of its action and that it cannot count on American economic and military help to sustain its ''ownership'' of the Golan land. Threatening a cutoff of aid -- or cutting it -- is not pleasant business. But, at a time of such pressures on the federal budget, the American people may well wonder why they should continue supporting Israeli policies which are inimical to US interests.
This is not to fail to appreciate Israel's anxieties about the direction of US policy in the Middle East, including a tilt toward Saudi Arabia, and Israel's desire to compensate for recent diplomatic setbacks. Nor does it absolve Syria and other Arab parties of responsibility for provocative acts and failed opportunities to make peace. But Prime Minister Begin has taken an illegal step which cannot but add to instability in the Middle East and which seems to say that Israel intends to live by military might rather than by the rule of world law.
Such a policy can never turn ''enemies into friends.'' On the contrary, it is a recipe for animosity and conflict.The brave people of Israel should want to turn back from this perilous course.