WARSAW, Poland — When Poland's fractious parliament cobbled together a new government in February, lawmakers kept the pact a secret from most mass media. They permitted the initial ceremony to be broadcast exclusively by affiliates of Radio Maryja, a Catholic broadcaster.

Accused of hostility toward Jews, gays and ex-communists who ruled Poland until recently, the network reaches an estimated 4 million Poles. Most are rural, elderly Catholics who feel left behind by the free market transformation of Poland since the fall of the Iron Curtain.

For nearly a decade, Radio Maryja (pronounced Maria) served primarily as a voice for opposition parties and others on the political margins. But these days, it has become the preferred medium of Poland's president, Lech Kaczynski, and his twin brother Jaroslaw, the de facto parliamentary leader.

Radio Maryja's aggressive support of the Kaczynski brothers and their Law and Justice party during last fall's election helped propel the two into power. That has given the Catholic station an outsized influence on affairs of state, critics say. Secular parties and even the Vatican say that role could prove dangerous for Polish democracy.

Although 96 percent of Poland's 38 million people identify themselves as Catholic, the country's post-Cold War political model maintains a strict autonomy between church and state.

On Thursday, during the start of a four-day visit to Poland, Pope Benedict XVI said the church should stay out of politics. "The priest is not asked to be an expert in economics, construction or politics," the pope declared. "He is expected to be an expert in the spiritual life."

That came on top of a sharply worded statement from the Vatican expressing "grave concern" over the radio service and its relationship with the government.

The statement came shortly after a Radio Maryja commentator accused Jews of profiting from "the Holocaust business" and complained that Jewish groups were "humiliating Poland internationally by demanding money" for property confiscated during World War II.

So far, Polish church officials have shown little inclination to tone down Radio Maryja, which is operated by Catholic priests from the Redemptorist Order. In response to the Vatican's criticism, the bishops formed a council to work with the Redemptorists to advise the station on programming, but also issued a statement praising Radio Maryja for its "great evangelizing work."

Station founder Tadeusz Rydzyk apologized to listeners if they were offended by the allegedly anti-Semitic broadcast. But Stanislaw Michalkiewicz, the commentator who criticized Jews, is still on the air. He denied his remarks were anti-Semitic.

"Accusing me of anti-Semitism was just a way of changing the subject," he said. "My program became a pretext to attack Radio Maryja, because the existence of Radio Maryja is a problem to some groups in this country."

Andrzej Rychard, a sociologist at the Polish Academy of Sciences, said Radio Maryja has a dedicated listenership of devout Catholics who feel marginalized and ignored by political parties.

During the campaign last fall, Radio Maryja helped spread a report that a grandfather of presidential candidate Donald Tusk had served in the German army during World War II. Tusk countered that his grandfather, like many Poles, was forced into the German uniform. But the report eroded his lead in the polls and he ultimately lost the election to Lech Kaczynski.