MANAGUA, Nicaragua — In the long, bitter feud between his church and the Sandinista government, Cardinal Miguel Obando y Bravo has often played on his humble origin and popularity in the countryside. A widely circulated church poster shows the stocky, dark-skinned cleric in a cowboy hat, riding a burro into a backwater town to say Mass.
Not surprisingly, the image was appropriated by U.S.-backed Nicaraguan rebels to seek support for their rural insurgency. They added the legends "Christianity Si, Communism No" and "Cardinal Obando Is With Us."
Until recently, the rebels monopolized the Roman Catholic patriarch as a propaganda symbol while government officials vilified him as the "Contra cardinal."
Then, two months ago, the government tacked up its own poster of Obando in the rural war zones. It showed him shaking hands with President Daniel Ortega. The inscription appealed to rebel soldiers: "Come home. Accept amnesty."
The words were deceptive: Obando has not urged the Contras to surrender. But the conciliatory image signaled a dramatic shift for the Sandinistas' leading critic to a new role as peacemaker in the seven-year-old conflict.
The handshake was photographed when Ortega named Obando head of the National Reconciliation Commission to monitor compliance with the Aug. 7 Central American peace accord. Last week, the government reversed a longstanding policy of refusing contacts with rebel leaders and asked the 61-year-old cardinal to mediate talks on a cease-fire.
Obando, who was accepted at once by the Contras, got the backing of Nicaragua's other bishops Wednesday to launch his mission. On Thursday, he traveled to Washington, where Sandinista and rebel leaders were gathered separately for the General Assembly of the Organization of American States.
"I am going to sound out the parties in conflict to see if it is possible to achieve a truce," he told reporters in Managua.
The quickly unfolding peace process is a personal vindication for Obando, whose years of pleading with the government to talk to Contra leaders has been a major source of church-state friction. It has also put him under more government pressure than ever to persuade the Contras, who revere him as a hero, to stop fighting.
Diplomats here list many factors that pushed the Sandinistas to the peace table: a failing economy, Soviet reluctance to pledge unlimited aid, military pressure by the Contras and the threat of renewed U.S. funding for them.
Equally important, the regional peace accord, drafted by President Oscar Arias Sanchez of Costa Rica, offered the Sandinistas a recognition of their constitutional order in exchange for press freedom and other democratic reforms that they apparently feel they can live with.
"Before August, the Sandinistas saw Obando as nothing more than a threat, the only man of equal stature who could challenge them," said a Western ambassador here. "But with the peace accord, he is suddenly their ideal mediator. He lends credibility to a process that gives them legitimacy and could shut off the Contras."
The talks appear to offer the best hope yet for ending a conflict that has claimed more than 20,000 lives. Working in Obando's favor is his authority as spiritual leader of Nicaragua's Roman Catholics, who make up 85% of the population.
The cardinal has remarked privately that he and Ortega have good reason to settle the conflict, because they may hold their current jobs long after Arias, other regional leaders and President Reagan leave the public stage.
"He is very sure of himself," said Luis Humberto Guzman, an opposition leader. "He knows that if he cannot fix all this, nobody can."
Obando was born in the mining and ranching town of La Libertad to a gold miner and a peasant woman of Indian descent. It is also the birthplace of Ortega, who is 20 years younger.
The Obando family was poor but scraped to send young Miguel to a seminary in El Salvador. He joined the Salesian order in 1958 and taught for a decade before returning to Nicaragua. He has been archbishop of Managua since 1970.
An outspoken critic of ousted President Anastasio Somoza, the archbishop was called upon twice to mediate when Sandinista insurgents seized large numbers of hostages, first in 1974 at a businessman's Christmas Party, then in 1978 at the National Palace. The hostages were exchanged for Sandinista prisoners, including Ortega.
Obando had an inflexible rule as a mediator: Once one side made a demand, it could not be changed. Thus, in the 1974 siege, he refused to add Rene Nunez's name to the prisoner-exchange list when the Sandinistas belatedly realized that Nunez was under arrest. Nunez, now the government official in charge of relations with the church, remained in jail two more years.
After the Sandinistas toppled Somoza in 1979, Nicaraguan bishops issued a letter saying they found no objection to the revolution's socialist goals.
Against Marxist Teaching