Four Democrats and Republican Supervisor Nancy K. Falck joined forces to defeat a proposal by a political opponent of Falck's who wants to build a Christian school in Fairfax County.

The application by Robert L. Thoburn, a conservative who is running as an independent against Falck for the Dranesville District seat on the Board of Supervisors, failed on a 5-to-4 vote late Monday night.

A virtually identical application by Thoburn was defeated by the board on a tie vote two years ago after county staff members warned it could pose a threat to the environment. The staff warnings were essentially unchanged Monday.

This year, with elections three months away, the Thoburn proposal was debated in a politically charged setting, with conservative members of the board jittery about the impact of the Christian Right in the balloting.

All nine supervisors will be on the ballot Nov. 3.

In an interview yesterday, Thoburn called Falck's vote "unbiblical," explaining that "God owns the land and I think we are his stewards." He added: "When the government controls {property} that way, what does ownership really mean?"

Asked to respond, Falck said: "Oh, goodness, I can't comment on that kind of disorganized commentary. That doesn't compute."

Falck has said she opposed the application because the school would be built near a flood plain and could threaten nearby streams.

In addition to Falck, the supervisors who opposed the proposal were Democrats Katherine K. Hanley of Providence District, Audrey Moore of Annandale District, Martha V. Pennino of Centreville District and Joseph Alexander of Lee District.

The four Republicans who voted for the application were board Chairman John F. Herrity and Supervisors Thomas M. Davis III of Mason District, Elaine McConnell of Springfield District and T. Farrell Egge of Mount Vernon District.