In a soon to be published book, "I Koch -- A Decidedly Unauthorized Biography," New York's Mayor Edward I. Koch is quoted as calling Rep. Ron Dellums (D-Calif.) a "Zulu warrior" and a "Watusi from Berkeley."

Koch admits the words are his. He says he intended them as compliments. He called Dellums after the quotation became public to tell the congressman that Watusis are "strong and tall" and the Zulus an "elegant and stylish" people.

Sure. And "Hymie" is a Jewish name.

According to Jack Newfield, a Village Voice writer who was the source for the quotation, Koch used the tribal references in 1976 during an acid volley against U.S. congressmen he felt were trying to reduce U.S. aid to Israel.

"He was specifically focusing on Dellums," Newfield said, "ignoring the substance of what Dellums had to say and then he called him a 'Watusi from Berkeley.' It was unmistakably hostile, derogatory and insulting. It was meant to be."

Dellums has decided to downplay it. The Berkeley congressman who has fought to avoid being labeled a "black militant" or the "congressman in bell-bottoms" is afraid that a personal response to Koch would allow his colleagues to dismiss him as an overly sensitive, angry black man.

But the incident begs comparison with the outcry last year when it was reported that Jesse Jackson privately referred to Jews as "Hymie" and rationalized it as a practice left over from his childhood.

In fact, Koch, in his role as a Jewish leader, led the way in condemning Jackson as an anti-Semite, largely on the basis of the "Hymie" comment. With that as his whip, Koch aired his suspicions that Jackson was an anti-Semite who favored Middle East policies that are antagonistic to Israel's best interests. His proof? The "Hymie" quote, Jackson's ties to Israel's enemies, the dark-skinned people in the Middle East. Jackson hugged Yasser Arafat, Koch reminded his audiences before urging unsuccessfully that Jackson not be allowed to speak at the Democratic convention.

Now Koch is in the hypocrite's corner. If he was so quick to throw stones at Jackson, he has no exemption from being stoned. No matter how expertly he dances away, by quickly admitting his intemperate words and calling Dellums to explain it all, he can't expect anyone to believe in his gut that he was complimenting the congressman.

Koch, who is running for reelection, should be haunted and harassed for every awful racist word revealed in his attack on Dellums. He should be questioned about it at every campaign stop.

Few would suggest that Jackson not be held accountable for his remarks. Why should it be different for Koch? There is no acceptable double standard on bigotry. Why don't Jewish leaders, in particular those who condemned Jackson at the hint of bigotry, condemn Koch?

Or can one group of Americans be freely slandered by a public figure while any hint of bigotry toward another group, in private conversation, is cause for moral outrage?

While proof of Jackson's animus toward Israel may lie in symbols, there is direct evidence of Koch's distaste for blacks. In a fiscal crunch he chose a Harlem hospital to be closed. After blacks gave him 60 percent of their vote in his first Democratic primary -- a runoff against Mario Cuomo -- he failed to support even moderate, establishment black politicians, stifling the growth of black political power in New York.

In 1981 he opposed David Dinkins, the city clerk, in his bid for Manhattan borough president. In 1982 he backed Alfred DelBello for the state's lieutenant governor's seat when Carl McCall, a moderate black candidate was running.

When it came to naming a superintendent for the New York City public schools, Koch chose Robert Wagner Jr. over Thomas Minter and Anthony Alvarado, a black and a Hispanic, respectively. Wagner was later denied the post because the state education commissioner found him to be unqualified for the job, having never taught school and lacking the necessary postgraduate degrees.

I wonder whether there will be a spate of newspaper articles casting doubt on the the ability of Jewish reporters, in a town with a large Jewish population, to cover a Jewish mayor. It might seem crazy, but just such articles were written about black reporters after the Jackson incident.

But seriously, the absence of Jewish outcry at Koch's behavior toward blacks and his foul description of a black congressman amounts to the Jewish community's turning a blind eye to the sins of their own. The issue is not that Jewish leaders should condemn Koch so much as why they don't feel compelled to do it.

Not all Jews are defenders of Koch. Before the Dellums' name-calling became known, Rabbi David Saperstein of the Union of American Hebrew Congregations talked about Koch at an NAACP convention in Dallas:

"It is true that we have our ADL (Anti-Defamation League), and our Morris Abrams (vice-chairman of the Reagan administration's civil rights commission), and Ed Kochs. . . ," he said. "But make no mistake about it: to the majority of Jews and Jewish organizations their views are wrong."

More Jewish leaders need to say the same and say it publicly and loudly.