PAT ROQUE / AP Carlos Celdran holds on prison bars inside the detention cell in Manila,, Oct. 1, 2010.

*This story was updated at 2:21 a.m. Feb. 7, 2013.

Damaso. That was the one-word message, painted on a placard, that activist Carlos Celdran delivered to a group of bishops in Manila Cathedral in a 2010 protest. To many Filipinos, the meaning was instantly clear: Padre Damaso is perhaps the most famous literary character in the Philippines, a corrupt and abusive Spanish priest who is the villain of Jose Rizal’s 1887 novel, Noli Me Tangere. Celdran had barged into the cathedral to protest the church’s efforts to defeat the Reproductive Health (RH) bill, which provides government funding for contraception and sex education. After more than a decade of bitter feuding, the bill was finally signed into law in December. It was a shocking victory, even for many supporters, and a sign that the church was losing some of its sway over the political affairs of a country that is 80% Catholic.

Last week, however, the church and its faithful had a message of their own: not so fast. As a result of his Damaso protest, Celdran was convicted by the Metropolitan Trial Court in Manila for violating an obscure provision of the Revised Penal Code, Article 133, which proscribes against “offending religious feelings.” Free on bail, Celdran awaits sentencing for a term of up to 13 months in prison. Human Rights Watch researcher Carlos Conde called the decision “a setback for free speech in the Philippines.” Article 133, dating back to 1930, was carried over from the criminal code of the Spanish colonial period, which ended in 1898. Celdran’s case is the first time the law has been taken to trial and ruled upon. “I didn’t even know this law existed,” said Conde.

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Celdran’s case has quickly turned into a referendum on the role of the church and the limits of free speech in the Philippines. Once virtually nonexistent, the line between church and state is being examined more closely than ever before, thanks in part to reform-minded President Benigno Aquino III and a new generation of social-media-savvy critics. The incident has also become a vehicle for re-examining the country’s penal code, which is littered with several other outdated provisions. A bill seeking to repeal Article 133 has already been introduced by Senator Pia Cayetano. In a note accompanying the bill, filed on Tuesday, the Senator wrote: “Freedom of speech and expression is essential to a sovereign state. In fact, the curtailment thereof has been one of the main reasons for revolts in the country throughout Philippine history.”

Perhaps that’s why the case has generated so much interest. The strange charge has helped turn Celdran into something of a cause célèbre in the Southeast Asian nation, inspiring Facebook support pages and the Twitter hashtag #FreeCarlosCeldran. The 40-year-old performance artist is already a local celebrity, best known for Walk This Way, a walking tour of Manila that TIME described as “filled with the kind of insight that only a native raconteur can provide.” A statement of support has even come from President Aquino, who was instrumental in the RH law’s passage. The President said, somewhat carefully, that he “may sympathize with Mr. Celdran’s position.”

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The church is also treading delicately around Celdran’s case. The Archdiocese of Manila issued a statement clarifying that it had no part in the prosecution of Celdran, even though it was “deeply disturbed” by his act. The powerful Catholic Bishops’ Conference of the Philippines has also distanced itself from the case, saying it has already forgiven Celdran. It was in fact a Catholic layperson, attorney Ronaldo Reyes, who pursued the case on behalf of the state. Harry Roque, a law professor at the University of Philippines, said Article 133 is a form of lèse-majesté and called it “an archaic provision which no longer has a place when the current constitution and human-rights laws now recognize freedom of expression.” Roque is currently in the midst of a different high-profile legal case, a challenge to the so-called cybercrime law, which contains sweeping and vague libel provisions that have sparked an enormous public outcry. (The libel laws are also a holdover from the Spanish penal code.)

What’s happening in the Philippines is not a full-fledged revolt but a re-examination of some of the country’s long-held orthodoxies. The biggest question is what role the church should play in national affairs. Hard-line supporters are already gearing up for challenges to the church’s authority. Jo Imbong, legal counsel for the Catholic Bishops’ Conference of the Philippines, said the RH law’s passage has “increased the resolve of Catholics to stand their ground.” There is also a moderate strain of clergy and Catholic laypeople that supported the RH law and has been outspoken regarding the Celdran case. “The Catholic Church is pervasive through the Philippine psyche in an absolute manner,” said Celdran, who himself identifies as Catholic.

For now, Celdran continues to lead his Walk This Way tour several times a week. On a recent outing, he did not mention his legal troubles to his audience of about 50, a mix of foreign tourists and Filipinos. But after the tour was over, several people approached him to offer words of support and pose for photos — one even brought a miniature “Damaso” sign for Celdran to hold up. Despite the threat of imminent jail time, Celdran maintains an optimistic take on not only his legal troubles but also on the future of the Philippines. “I’m kind of lucky that I’m in a society that I truly believe in my heart is secular, progressive and logical,” he said. “And I feel like it is very fortunate for me to be in a position that can prove that about our nation.”

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