A prophet, says Yehezkel Landau of Jerusalem, a graduate of both Harvard University and Harvard Divinity School, is a person who chastises his own community. The chastising industry -- low-paying, nonunion work -- had its glory days in Israel when Jeremiah, Amos, Isaiah and others were shouting to the deaf that the commands of God were not being obeyed. In the Israel of 1985, Yehezkel Landau is dealing in the kind of prophecy that antiquity's rebel Jews were filling the Bible with. To his credit, he is as much an outcast as they were.

At 36 and a dual citizen of Israel and the United States, Landau came to Washington last month to give encouragement to those Americans who want to see the strong peace movement in Israel grow stronger. The nation that flamed with promise a generation ago has become another of the world's warrior states.

Of late, the policies of the coalition government of Shimon Peres and Yitzhak Shamir have created a climate of violence that could keep busy a dozen Landaus. Three examples, among many, are enough. Israel's October raid in Tunisia on the headquarters of the PLO left at least 60 Palestinians and Tunisians dead, with another 100 injured. The U.N. Security Council, on a 14-0 vote, condemned the raid. Bombs were dropped from planes marked with the Star of David. Since August, the Israeli government has been censoring and harassing the Arabic press in the occupied West Bank and Gaza. The New York-based Committee to Protect Journalists, citing more than a half-dozen recent bullyings against Arab journalists, calls the attacks unwarranted. A research study from the Council on Hemispheric Affairs last week reported that Israel is now the third largest arms merchant in Central America. Since the early 1970s, it has sold more than $1 billion worth of weapons -- everything from warplanes to napalm -- to right-wing dictatorships.

This, and more, says Landau, is "our spiritual disease." In the religious Zionist peace movement, Landau has 1,500 Israelis aligned with his organization Oz VeShalom (strength and peace). It is a teaching, service and public-information group founded in 1975 in response to other religious organizations that mixed ideology and faith to justify exclusivist territorial claims. Israel's peace movement peaked after the massacre of Palestinians at the Sabra and Shatila refugee camps near Beirut. More than 400,000 citizens turned out for what was the largest demonstration in Israeli history. Peace Now, the organizing group, has held workshops for 5,000 Israeli children to teach them that cooperation with the country's Arab neighbors is a surer way to peace than military facedowns.

In Israel, Landau is a regular visitor to Arab groups. His religious Zionism makes room for Palestinian nationalism: "Israel and Palestine don't need to be mutually exclusive." He tells of speaking recently to a group of Palestinian teen-agers in the Arab section of Jerusalem: "One of the young women there has lived her whole life under military occupation. It's all she knows. When she thinks of Israel, she thinks of soldiers."

In the American mind, prophets are seen as forecasters. To the full-mooners, they walk in sandwich boards announcing that the end is near.

Landau, in a Jerusalem Post article, wrote that the prophets- of-doom kind of thinking "makes a mockery of any notion of salvation . . . To which prophetic vision should we look for inspiration and guidance -- the few cryptic passages in Scripture that mention God's wrath against the enemies of Israel, or the far more frequent exhortations against callousness and corruption?"

Landau chooses the second. He is clearheaded about his calling and appears to have a stockroom of energy to see him through a long future of earning less than $6,000 a year, his current wage. Prophets, he would agree at least in principle, need poverty. It keeps them rich in outrage.

It also helps them to be lean and spare of thought, as Landau is when explaining the two functions of a religious peace movement: prophetic and priestly. "The prophetic is to say that the state is corrupt and greedy and profits off violence and power, and that it has to repeat and change its ways. That's the classic prophetic critique. The priestly role is to transform people's emotional investments in fear, guilt and grief. That's where we are stuck now. We have to provide alternatives, political and social, that are emotionally genuine."

Landau's kind of language is well received in Israel's peace movement. The nation's leaders, hard-souled and unyielding, are renegades from the Israel of Isaiah. The October attack on Arabs 1,500 miles away in Tunisia, said Peres, "was an act of self-defense. Period." Landau doesn't believe in bombing raids to resolve political conflicts. He takes the harder way, that of mutual forgiveness and reconcil- iation. Because of that, he is in a line of prophets. Israel is about the only place in the world where a rebel is also a traditionalist.