SAN JUAN CHAMULA, Mexico - On a recent Sunday morning, several dozen Mayan farmers packed the newly inaugurated Prince of Peace church, where a Protestant pastor discussed the importance of good works in the local Tzotzil language.
There was little remarkable about the service, except that it was being held in San Juan Chamula, a community as famous for its religious intolerance as its unusual blend of Roman Catholicism and ancient Mayan rituals.
Since 1974, more than 30,000 members of this fiercely traditional community in the southern state of Chiapas have been expelled for rebelling against local customs. Most were Protestant converts who refused to take part in the elaborate and costly Catholic rituals that form the backbone of Chamulan culture.
After Brazil, Mexico is home to the world's second-largest Catholic population - 88 million, according to the 2000 government census - and is viewed by Rome as a key hedge against the spread of US-based Protestant groups into the rest of Latin America.
But efforts by communities like San Juan Chamula to discourage conversions, even by expelling converts and torching their houses, have done little to stem the spread of Protestantism in Mexico. Instead, such campaigns - in violation of Mexico's Constitution, which guarantees freedom of religion - appear only to have fueled conversions by making Catholics appear intolerant.
The Protestants have made particular inroads among the country's 10 million Indians. They woo converts by bringing doctors and schools to impoverished indigenous communities and by distributing Bibles translated into most of the country's 62 Indian languages. According to census figures, 7.3 percent of Mexicans over the age of 5 are Protestants, up from 4 percent in 1990. Chiapas, with a 30 percent indigenous population, has a larger share of Protestants than any state at 23 percent.
''It's ironic that where the persecution [of Protestants] is the greatest is where they have made the most converts,'' said Abdias Tovillo, a Presbyterian minister and leader of a Chiapas-based group that defends Protestants' rights. Tovillo put the number of Protestants in the state at 40 percent, arguing that many converts were afraid to declare their religion to government census-takers for fear of being expelled from their communities.
Catholic church officials, aware that they are losing adherents, are increasingly looking to win back Indian communities. Crucial to that effort is Pope John Paul II's Mexico trip from July 30 to Aug. 2 to canonize the region's first indigenous saint, the Aztec Juan Diego. According to Catholic lore, the Virgin of Guadalupe appeared to Juan Diego on a hilltop outside Mexico City in 1531, 10 years after the Spaniards conquered Mexico. The Virgin Mary's purported apparition set the stage for the conversion of millions of Indians to Roman Catholicism.
The fact that the pope has insisted on making the trip despite his failing health is seen by many as a sign of a new focus in Rome on Latin America's Indians.
''There is no doubt that the Church has neglected indigenous peoples. ... In this trip, Pope John Paul II will demonstrate his concern for the misery in which today's Indians still live,'' said Manuel Zubillaga, a Mexican priest and member of the commission charged with consulting indigenous groups about the upcoming canonization.
Many critics say the Catholic Church has missed other key opportunities to bolster its presence in Indian communities. In Chiapas, efforts by Samuel Ruiz, the former bishop of San Cristobal de las Casas, to build solidarity among the region's Catholics almost got him expelled from the church. Ruiz, seizing on the grass-roots spirit of the 1962 Vatican II accords, ordained nearly 400 Indian deacons to minister to remote villages that lacked their own priests.
But the Vatican saw the deacons and the several thousand Indian catechists as collaborators of the Zapatista rebels, the army of Mayan Indians that rose up against the Mexican government in January 1994. In February, the Vatican ordered Ruiz's successor, Bishop Felipe Arizmendi, to stop ordaining new Indian deacons for at least a five-year period.
''Throughout the colonial period, the major failing of the Catholic Church was that most of its faithful were Indians, but none of its priests,'' said Walter F. Morris, an American anthropologist based in nearby San Cristobal. ''Ruiz was trying to sidestep the problem,'' he said, by appointing Indians to lower-level church positions.
Arizmendi, who is considered more conservative than his predecessor, has focused on easing religious tensions in the region rather than trying to bolster an indigenous church.
''We recognize that there were times when we [members of the Catholic Church] were intolerant with those who dissented with the Catholic faith,'' he wrote last year in a paper on religious plurality in Chiapas, adding, ''Still today, there are cases of religious intolerance by Catholics toward those of other faiths.''
The first Protestant missionaries arrived in San Juan Chamula in 1934 led by American missionary William Cameron Townsend, founder of the Summer Institute of Linguistics. The California-based group, which is the world's leader in translating the Bible into native languages, was later expelled from the community. Other missionary groups followed, and their road into the Mayan communities has been paved with blood and countless expulsions.
Marcelino Cruz, 27, the pastor of the Prince of Peace church, converted to Presbyterianism in the early 1990s. He said he became disillusioned with the Chamulan brand of Catholicism after the local shamans failed to cure his sick father. In 1993, he was among 534 Chamulan Protestants forced to leave his community in the latest wave of religious expulsions.
The converts refused to be cowed. When the Catholics would not let them send their children to the town schools, they opened their own school last year in a nearby village. They have built five churches since 1994.
Chamula authorities acknowledge that times are changing.
''We're no longer expelling people. If they respect the traditions, we don't bother them,'' said Jose Gomez Gomez, the community's new mayor.
''If they start telling lies, we put them in jail,'' he said, thronged by villagers dressed in the community's traditional wool tunics and straw cowboy hats. ''Those who come to San Juan Chamula looking to make converts are the enemies of the people.''