A FIFTY-FOUR YEAR OLD Korean immigrant is currently swabbing trays and loading dishes into washers at a federal prison in Danbury, Conn., and millions of people are unhappy about it. The man is the Rev. Sun Myung Moon, founder and leader of the Unification Church, which numbers two to three million followers worldwide, and he's serving an 18-month sentence for tax conspiracy and tax fraud.

The government claims that Moon failed to pay taxes on $162,000 interest on a $1.8 million Chase Manhattan Bank account. Moon says that he was holding the money in trust for his church, an established legal practice known as corporation sole, and that the money should therefore have been tax-exempt. (Curiously, Moon did pay personal taxes on the bulk of the account).

Two years ago, the government proved to a jury's satisfaction that Moon used the Chase Manhattan account to purchase stock in iron and paint companies and a Washington bank, to pay for clothing and private schools for his children, and to buy such sundries as gold watches for himself and his friends. IRS agents researched the case for five years and the government spent two years prosecuting it. The estimates for the cost of prosecution and defense range up to $6 million.

But while the government insists that it had a solid and straightforward legal case against Moon, it has been unable to dissuade religious leaders and civil libertarians from their belief that the conviction is symptomatic of a broader governmental attack on religious autonomy.

Scores of national religious leaders have spoken on Moon's behalf, defending less the vagaries of his particular case than the issues of religious freedom the trial has raised. And figures as politically diverse as Joseph Lowrey, president of the Southern Christian Leadership Conference, and Dr. Tim Lahaye, president of the Moral Majority of California, have joined to spearhead a group of ministers who have pledged to spend a week in jail with Reverend Moon. This unusual commitment indicates the depth of their belief that Moon's prosecution was a disguised persecution.

Religious figures base their argument on the first amendment--which is unfortunately so broadly phrased that interpretive battles over it are endemic to the American judicial system. The amendment begins: "Congress shall make no law respecting an establishment of religion or prohibiting the free exercise thereof." However, the Moon case attests to the ambiguity of the Constitutional guarantee--for all the government's determination to prosecute Moon, the controversy has sparked a firestorm of articles, rallies, charges and countercharges that is only gradually diminishing.

The religious community sees the Moon case as a strong indication that the government plans to interpret those 16 words as narrowly as possible, allowing churches free exercise only if they meet government standards. Harvey G. Cox Jr., Harvard's Thomas Professor of Divinity, voices a common concern when he notes the implications of the IRS having a say in how religions disburse their funds: "One can imagine in a future generation a politicized IRS deciding that the Catholic Church shouldn't speak out against nuclear war. Or anything else--there's no limit."

One of Cox's fellow sponsors for a June Ad Hoc Committee for Religious Freedom rally in Boston was former Minnesota Senator Eugene McCarthy, who spoke to the same point.

I once suggested they put a sign up over the [IRS] office there saying Abandon the Bill of Rights, all you who enter here', because they have a different set of guarantees in that agency...we're now moving to where we'll have to say that the religion of the people is the religion of internal Revenue Service.

IRS FASCISM is not the least of the charges religious leaders have made against the government. Moon himself sounded the call to rhetoric when he stood on the steps of the United States Court House after his indictment in 1981 and declared "I would not be standing here today if' my skin were white and my religion were Presbyterian. I am here today only because my skin is yellow and my religion is Unification Church."

At first, the issue of selective prosecution appeared paramount. Earlier this year, when Idaho Congressman George Hansen updated his book about the IRS' abuse of power. To Harass Our People, he included a chapter summing up the Moon case. Hansen wrote that "From the beginning, it was evident that the government was relying for its case on the most damning facts possible-the unpopularity of the Moon church and the fact that Reverend Moon is an Oriental."

The government began investigating Moon in 1975, shortly after Senator Robert Dole (R-Kansas) wrote his "Many Kansans" letter to Donald Alexander, then Commissioner of the IRS, Dole requested an audit of the Unification Church's finances, and questioned whether the Church was "based on a bona fide religion or mind-control techniques." Dole offered as evidence the claborately phrased hearsay, "Many Kansans have advised me that a major purpose of the organization is the accumulation of wealth and power and not the practice or furtherance of a religion."

In June of this year Moon claimed before a Senate Subcommittee chaired by Orrin Hatch (R-Utah) that secret Justice Department memos prove three tax law experts recommended the IRS drop its six-year audit of the Unification Church "because there was no criminal case there." Moon urged that Hatch ask the Justice Department to make public these documents, which he claims show that the tax lawyers were twice overruled by a "high-level political appointee with no political experience."

Release of the documents, said Moon, "will show to the world that my prosecution was politically motivated and there was a criminal conspiracy by certain high government officials to 'get Reverend Moon.'" Senator Hatch promised to look into the matter, but Unification Church officials say they do not expect the Justice Department to release the documents.

BUT EVEN conspiracy theorists agree that whatever the government may have done clumsily, or done wrong, they chose a good scapegoat when they picked on Moon.