Bible study is no back-to-basics fad for the people in Mercer County, W. Va. The county's public schools have had "optional" Bible classes for some 43 years. School officials say the classes do not constitute "religious instruction" but are merely "literary and historical" courses. Still it's hard to see how the practice can survive the challenge brought by parents of eight Mercer County students.

The classes -- a half-hour a week in the lower grades and 50 minutes a day in high school -- are taught by members of the Bluefield Bible Study Association, all graduates of the Columbia (S.C.) Bible College. The school system neither selects nor certifies the teachers, but it allows high school students taking the course to earn credits toward graduation. (Beginning with this year's 9th graders, the course will be on a not-for-credit basis.)

Mercer County Acting Superintendent I. Sue Schmelzer said the complaining parents had approached her about alternative instruction for their children, "and that is what we were dealing with." But apparently the issue has moved beyond the question of alternatives to the more fundamental question of whether Bible study as practiced in the Mercer County schools is a violation of church-state separation.

"Some people make the complaint that we're teaching religion in the guise of literature," a Bible instructor at Bluefield High School told the Associated Press. "We're not. If the children ask religious questions, like do you have to be baptized to go to Heaven, I won't tell them. We don't touch areas like that."

Nice try, but hardly likely to pass muster with a Supreme Court that isn't persuaded by the religious neutrality of a "moment of silence" in public classrooms.

It's easy enough to believe that instructors from the interdenominational Bible Study Association make a serious effort to keep their instruction free of specific denominational implications. But it's hard to believe that anyone who cares as deeply about the Bible as these instructors apparently do could keep his lessons free of religious content -- or would want to.

"I can see how a non-Protestant might have a concern," Schmelzer admitted in a telephone interview. "You have to understand that we're deep in the heart of Appalachia, a part of the Bible Belt -- that's not my description; that's how the people here describe themselves. Bible study goes very deep into their culture here."

Schmelzer, who came to Bluefield from Iowa, declines to guess whether the matter will be settled short of a court fight or to give her own views on the question. On the one hand, Bible study is optional, with about half of the district's youngsters choosing not to take it. On the other hand, she acknowledges that, optional or not, the course might offend the religious sensibilities of some parents.

State Superintendent Tom McNeel is now trying to decide whether to attempt to settle the question on his own or refer it to the state attorney general. In either case, the answer seems forgone: the classes have to go.

It might have been a closer call if they were taught after school hours and not for credit. Certainly a case can be made -- pragmatically if not constitutionally -- that Bible study deserves as much protection as, say, aerobic dancing. But it seems clear that the good people of Mercer County, their 43-year tradition and noble intentions notwithstanding, have crossed the barrier that is supposed to keep the government out of religion.