The Supreme Court announced yesterday that it will hear two cases involving the display of the Ten Commandments on government property, setting the stage for rulings on an issue that has divided the public and the lower courts for more than two decades.

In a brief order, the court said it would review a federal appeals court ruling that upheld a six-foot-tall monument to the commandments on the grounds of the Texas state capitol in Austin, plus another ruling that barred an exhibition of the commandments with other historical documents in a Kentucky courthouse.

The court last addressed the subject in 1980, when it struck down, 5 to 4, a Kentucky law that required the posting of the commandments in public school classrooms. The court ruled that the law had "no secular legislative purpose."

Lower courts have since been the scene of protracted legal warfare as advocates of church-state separation have clashed with those who argue that the 1980 ruling does not bar all government-backed displays of the commandments.

"Given the amount of litigation surrounding this issue in recent years, it is not surprising that the Supreme Court would want to clarify often-conflicting rulings below," said Steven R. Shapiro, legal director of the American Civil Liberties Union.

Lower courts have issued more than two dozen rulings in varying circumstances, but until yesterday the Supreme Court had refused to step in, turning down six petitions for review of the matter. One involved the case of Roy S. Moore, who was forced from his position as chief justice of the Alabama Supreme Court last year after refusing a federal court order to remove a commandments monument from the state courthouse in Montgomery.

Now, however, the pressure for Supreme Court action appears to have become irresistible.

There are more cases in the court's pipeline. In addition to the Texas case, Van Orden v. Perry, No. 03-1500, and the Kentucky case, McCreary County v. ACLU of Kentucky, 03-1693, there are three pending cases on the display of the commandments in public schools.

Politically, public display of the Ten Commandments is an issue that energizes the liberal and conservative bases of the Democratic and Republican parties, respectively.

Lawsuits to remove the commandments have often pitted the ACLU and its supporters against small-town governments backed by conservative religious legal groups. The American Center for Law and Justice, a conservative legal advocacy group, says it is involved in 20 Ten Commandments cases in the lower courts, including one related to a monument to the commandments in Frederick.

Legally, the Supreme Court cases raise issues similar to those in the court's last high-profile brush with a church-state controversy: last term's challenge to the phrase "under God" in the Pledge of Allegiance, which schoolchildren recite at the beginning of each day.

The court ducked the issue at the heart of that case -- whether "under God" impermissibly crossed the church-state line -- and upheld the pledge on technical grounds.

Just as California atheist Michael A. Newdow argued that "under God" is an unconstitutional state-sponsored religious affirmation, opponents of public displays of the Ten Commandments argue that they impermissibly put an official imprimatur on one particular religious belief.

Backers of displaying the commandments say it is not necessarily a governmental religious statement, but rather, in the right context, an acknowledgment of the role Judeo-Christian norms played in the development of Western civilization and American law.

They note that a depiction of Moses carrying the Ten Commandments adorns the walls of the Supreme Court, in a frieze that includes Hammurabi, Solon and other historical lawgivers.

A similar point was made by supporters of "under God," including the Bush administration and congressional leaders from both parties.

In the Texas case the court granted yesterday, the state argues that its monument, placed among others on the capitol grounds, has no religious purpose or effect, but expresses the commandments' "historic and secular role as a foundational text for Western culture and legal codes."

In the Kentucky case, McCreary County responded to a lawsuit against a framed copy of the commandments in its courthouse by surrounding the Decalogue with an array of documents including the Declaration of Independence and the Magna Carta. This, the county maintains, shows the display's "secular purpose."

Separately yesterday, the court entered another religion-related area when it agreed to hear a case testing the federal Religious Land Use and Institutionalized Persons Act. That 2000 statute prohibits any "substantial burden on the religious exercise" of an institutionalized person unless the restriction is clearly justified and carefully limited.

The case involves charges by current and former Ohio state prisoners that officials denied them the freedom to practice Wicca and Satanism.

The prisoners said that the prison violated the legislation by denying them access to religious literature and to such "ceremonial" objects as medallions, and that this was a "substantial burden" on their free exercise of religion.

The Bush administration, which supports the legislation, had urged the court to take a different case on the same issue, but the court rebuffed that request.

In siding with the prison authorities, the Cincinnati-based U.S. Court of Appeals for the 6th Circuit struck down the law, ruling that it amounted to a government endorsement of religion.

The case is Cutter v. Wilkinson, No. 03-9877.

Staff writer Fredrick Kunkle contributed to this report.

Texas Attorney General Greg Abbott is shown by a monument to the Ten Commandments near the state capitol in Austin. Abbott has said he will argue the state's case before the Supreme Court.