But it is a different matter when officials prominently display the biblical Commandments so that all can see their religious message, he said.

"Context matters," Souter said.

That distinction pleased advocates of church-state separation. "Everyone interested in religious freedom should want the government to stay neutral when it comes to religion," said Ralph Neas, president of People for the American Way.

But leaders of several Christian groups attacked the Kentucky decision. Roberta Combs, president of the Christian Coalition of America, called it "tyrannical" and said it "showed once again the nation's top court is completely out of step with the American people."

The justices in the Kentucky case majority seemed determined to hold the line.

"The divisiveness of religion in current public life is inescapable," Souter said. "This is no time to deny the prudence of understanding the Establishment Clause (of the First Amendment) to require the government to stay neutral on religious belief, which is reserved for the conscience of the individual."

He and Justice Sandra Day O'Connor said they saw a danger in allowing the government to take sides on religious matters.

"Allowing the government to be a potential mouthpiece for competing religious ideas risks the sort of division" that the Constitution sought to avoid, O'Connor said. "Those who would renegotiate the boundaries between church and state must therefore answer a difficult question: Why would we trade a system that has served us so well for one that has served others so poorly?"

Justices John Paul Stevens, Ruth Bader Ginsburg and Breyer joined them.

The ruling drew a powerful dissent in the courtroom from Justice Antonin Scalia, who accused his colleagues of ignoring religion's role in the nation's founding.