ASHINGTON, Feb. 25 — The Supreme Court ruled Wednesday that states that subsidize secular study at the college level may withhold the scholarships from students preparing for the ministry.

The 7-to-2 decision, upholding the eligibility requirements of the Promise Scholarship program in Washington State, was a setback for advocates of using publicly financed vouchers to pay for religious school tuition. Joined by the Bush administration, advocates of "school choice" programs sought to use this case to establish a broad principle that an institution's religious affiliation should not make it ineligible to participate in general programs of government aid.

Those deeper implications had made this case one of the most closely watched of the court's current term. Two years ago, the court ruled in a case from Ohio that extending voucher programs to cover parochial school tuition was constitutionally permissible. The Washington case raised the further question of whether it was not only permissible but, at least under some circumstances, constitutionally required, an urgent question given that voucher proposals have run into political and legal obstacles in a number of states and have spread much more slowly than advocates had hoped.

The opinion by Chief Justice William H. Rehnquist did not address school-choice programs directly and left important questions to be answered in future cases. But it was a decisive rejection of the proposition that a government that subsidizes a secular activity must necessarily, as a matter of the constitutional free exercise of religion, subsidize the comparable religious activity as well.

The chief justice said the distinction that Washington made in its five-year-old scholarship program reflected the state's longstanding interest in avoiding an "establishment" of religion, rather than hostility or animus toward religion. He said that while the Washington Constitution mirrored the prohibitions found in many of the early state constitutions against using tax money to support ministers, it was nonetheless quite protective of religion in many respects.

"The state has merely chosen not to fund a distinct category of instruction," he said, adding that "training for religious professions and training for secular professions are not fungible." If the state wanted to pay for religious training, it could do so, he said, adding that the case simply demonstrated that "there are some state actions permitted by the Establishment Clause but not required by the Free Exercise Clause."

New York, New Jersey and nine other states in addition to Washington have scholarship programs that bar the use of the money for religious training. A similar prohibition in Michigan is under challenge in federal court there.

In a dissenting opinion, Justice Antonin Scalia, joined by Justice Clarence Thomas, objected that the court was validating antireligious discrimination and reflecting "a trendy disdain for deep religious conviction."

"Let there be no doubt: This case is about discrimination against a religious minority," Justice Scalia said, referring to Joshua Davey, a member of the evangelical Assemblies of God denomination and the student who brought the case.

"What next?" Justice Scalia asked. "Will we deny priests and nuns their prescription-drug benefits on the ground that taxpayers' freedom of conscience forbids medicating the clergy at public expense?"

The Washington Legislature devised its scholarship program in 1999 to reflect a provision in the Washington Constitution that bars the use of public money to support "any religious worship, exercise or instruction." Consequently, students who were otherwise qualified for the scholarships on the basis of academic merit and financial need were ineligible if they wanted to use the money to major in theology and train for the ministry.

On the other hand, students did not forfeit their eligibility simply by taking courses in religion or by attending a religious college, as long as they pursued a secular major there.

Thirty-six states have constitutional barriers similar to Washington's to supporting religious institutions with public money, and these have proved to be substantial obstacles to the spread of the school-choice movement. Supporters of vouchers had argued that these provisions were the product of bigotry.

The exclusion of theology majors was challenged by Mr. Davey, who in 1999 enrolled in a college affiliated with the Assemblies of God and declared a major in pastoral ministries. Although he was otherwise qualified to be a Promise Scholar and to apply his $1,125 scholarship to his expenses at Northwest College in Kirkland, Wash., officials there told him that because of his intended major, he could not have the money.

Represented by the American Center for Law and Justice, a law firm affiliated with the Rev. Pat Robertson, Mr. Davey sued the state, asserting his constitutional rights to the free exercise of religion, free speech and equal protection. He lost in federal district court in Seattle. But the United States Court of Appeals for the Ninth Circuit, in San Francisco, ruled in his favor in 2002, holding that the state had singled out religion for unfavorable treatment.

Gov. Gary Locke of Washington appealed to the Supreme Court.

Mr. Davey, meanwhile, continued his college education, graduated at the top of his class and is now in his first year at Harvard Law School.

The Bush administration entered the case on Mr. Davey's side to seek a decision helpful to the president's initiative under which religious organizations can receive federal money to provide services. Scott McClellan, the White House press secretary, said Wednesday that "the president will certainly continue to work to make sure that faith-based groups are not discriminated against." Mr. McClellan called the ruling "very narrow."

It was narrow to the extent that it specifically addressed professional training for the ministry at the college level. It therefore left open the question of whether elementary and high schools that offer a general education, though with religious sponsorship, can be carved out from a general voucher program.

"The court went out of its way to limit the context," said Clint Bolick, vice president of the Institute for Justice, a strong supporter of vouchers that filed a brief in the case. Mr. Bolick's organization is handling school-choice cases in Colorado and Florida, where programs were struck down in state court. He said in an interview that he would take those cases to the Supreme Court, if necessary, to test the limits of the ruling Wednesday in Locke v. Davey, No. 02-1315.

Barry Lynn, executive director of Americans United for Separation of Church and State, which supported the state, agreed that the decision was not the court's last word. But Mr. Lynn said its significance lay in the court's rejection of "the effort by religious conservatives to use this as a breakthrough case for their theory of free exercise, that if you fund the secular you must fund the religious."