Cape Town — The remarkable thing about South Africa's latest publicized racial incident is not that it happened, but that many white South Africans reacted so violently to it.
It happened in a little town called Clanwilliam, which is just a small dot on the South African map. The town's population is 3,902 - 1,250 whites, 2,626 Coloreds (people of mixed race) and 26 Africans, all neatly segregated according to law.
Clanwilliam's main street is laid with concrete to keep down the dust. There is one hotel and one high school. The town boasts in South Africa's municipal almanac that its wild flowers in spring are ''beautiful'' and the fishing in nearby Elephant River is ''famous.''
The most imposing building in town is the Afrikaans Dutch Reformed Church, to which most of the town's whites belong.
The church's minister, the Rev. Gideon Boshoff, is the man who proctors when local students studying for degrees by correspondence write examinations set by the University of South Africa.
This year there were four students writing the Afrikaans examination. Three are teachers - and one of them, Johannes Joorst, is the principal of a nearby junior school. The students chatted outside the church while they waited for Mr. Boshoff to let them into the vestry.
The minister arrived, greeted the students, and led them inside. But there were only three places set in the vestry. And before Mr. Joorst could sit down, Mr. Boshoff told him: ''You can't sit here. Come with me, you can write your exam in the kitchen. It is very pleasant there.''
Mr. Joorst is a Colored man and the other students are white.
As Mr. Joorst was led away, one of the other students said: ''I know for sure there is going to be trouble about this.'' But she could hardly have realized how right she was.
The news broke first in a national Sunday newspaper. Many people shrugged when they saw it. After all, this sort of racism is endemic in South Africa. It has even been enshrined in law here.
Races are separated on the trains. They cannot live in the same suburbs. They certainly may not marry across the color line.
The leading Afrikaans church, the Dutch Reformed Church, defends apartheid (compulsory race segregation), although it has formally condemned ''racism.''
The main branch of the Dutch Reformed Church is virtually exclusively white - so much so that it has been commonplace for Colored mourners to be turned away from white funerals.
But the ''kitchen exam'' incident touched a raw nerve - even among many Afrikaners.
Granted old-style Afrikaner conservatives were surprised by the outcry. The minister was only doing his duty, they say. And his church committee rallied round him, praising his ''Christian guidance'' and pointing out that ''Colored people'' are allowed into the Clanwilliam church only with special permission and provided a white member of the congregation guarantees they will behave in an orderly fashion.
Nonetheless little Clanwillian was caught up in an uproar. Afrikaans newspapers have been inundated with letters from readers saying they were ''shocked,'' ''humiliated,'' and ''shamed.''
''It [the incident] is apartheid in its naked, ugly form, which we cannot anymore afford in our country,'' wrote Mr. Jannie Momberg, a leading Cape Afrikaner.
A letter signed ''believer'' from Cape Town wrote: ''The Reverend Boshoff preaches on Sunday that you must love your nearest like yourself, and on a Monday he apparently exemplifies something quite different.''
Even the ''Burger,'' the main Afrikaans newspaper in the Cape Province, has noted that public reaction has been ''overwhelming.'' Never before has an incident of this nature provoked such a flood of outraged letters, it said.
Some hopeful liberal Afrikaners claim the reaction is evidence of a deep stirring against racism in the national conscience.
As for the Rev. Gideon Boshoff, he says he cannot see what the fuss is about. He did what he saw was right, he says. But he adds: ''I can't expect everyone to understand.''