The Fairfax County Board of Supervisors last night effectively overturned a controversial 1984 ruling that had spelled out what activities may take place on church property.

That ruling by former Zoning Administrator Philip G. Yates had triggered a barrage of protest from church leaders and their followers, particularly because it would have required churches to seek special permission to operate shelters for the homeless. Although the county never enforced the ruling, critics called it an attempt to define church-state relations and limit the proper role of religion.

Yesterday, a parade of clergy and laymen denounced the ruling in a public hearing before the supervisors.

After nearly 50 speakers -- most fervent, some cautionary -- denounced Yates' ruling, the board effectively undid Yates' interpretation of the county zoning law by changing the zoning law. The vote was unanimous.

"This new ordinance is a giant step in the right direction," said Board Chairman John F. Herrity, a Republican. He called the Yates ruling "an attempt by an individual . . . to codify the relationship between church and state."

In contrast to the ruling, which had listed specific activities sanctioned for churches, the law enacted last night is broadly drawn, permitting uses of church property "in furtherance of . . . religion."

Although the supervisors had joined in the criticism of Yates' ruling, state law prevented them from overruling his interpretation of the local zoning ordinance.

Nearly 200 church leaders and their followers jammed the county board chambers for yesterday's hearing as some speakers opposed any law, some spoke for only the mildest of laws, and some scolded the supervisors and county staff and lectured them on constitutional protections.

"The church belongs to God and not to Fairfax County," declared B.W. Sanders, minister of the Bethlehem Baptist Church. "Do you honestly know what a church is supposed to do? If I were to ask you to write a job description for a church, what would you write?"

County supervisors were harsh in their assessment of the ruling by Yates, who has left the county for private employment, and the controversy it has engendered.

"This is one of the worst pieces of staff work I've ever seen coming out of the county," said Supervisor Thomas M. Davis III, a Republican. "It's wrong in every sense of the word."

Herrity was quick to agree. "The Board of Supervisors would like to take Interpretation 52," as the ruling is known, he said, "and burn it."

A few speakers at the hearing endorsed a proposed zoning ordinance that would have listed activities permitted on church property. They argued that such a law could strike a balance between the county's interest in protecting its neighborhoods and the churches' right to practise religion freely.

"We do not feel that churches should be granted immunity from county ordinances," said Alan Mayer, who represented the Fairfax County Federation of Citizens Associations.

But that proposal, which would have allowed religious services, religious study programs, choir practices, vacation bible schools "and other similar programs . . . " on church property, was criticized by most of the speakers and ultimately was shelved.

The phrase, "similar programs," drew fire from some opponents who said that the wording left it up to the county to define activities not specified in the ordinance.