A federal judge ruled Tuesday that a Louisiana state law requiring the Ten Commandments to be displayed in all public school classrooms is unconstitutional.

Lawyers for the state of Louisiana are asking a federal appeals court in New Orleans to immediately block a judge’s ruling ordering education officials to tell all local districts that a law requiring schools to post the Ten Commandments in classrooms is unconstitutional.

The ruling is probably the first in what could be a long legal fight for conservative Christian groups hoping to amplify public expressions of faith.