Citing the responsorial psalm for the day's Mass -- "Create a clean heart in me, O God" -- the Pope said that evil can be overcome only through a divinely inspired change of the human heart.
The Pope made note of the monument to Christ the King visible atop a nearby hill and observed that Christ's "kingdom does not stand on the power of his armies subduing others through force or violence. It rests on a higher power that wins over hearts: the love of God that he brought into the world with his sacrifice and the truth to which he bore witness."
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That message was consistent with Pope Benedict's frequently stated objections to strategies for social progress that blend Christian social doctrine with Marxism or other secular ideologies.
"The church is not a political power, it is not a party," the Pope told reporters on his flight to Mexico March 23. "It is a moral reality, a moral power."
In his Silao homily, the Pope did not specifically address any of Latin America's current social problems, but after praying the Angelus following the Mass, he recited a litany of ills plaguing Mexico and other countries in the region: "so many families are separated or forced to emigrate ... so many are suffering due to poverty, corruption, domestic violence, drug trafficking, the crisis of values and increased crime."
Speaking in the central Mexican state of Guanajuato, which was a stronghold of the 1920s Cristero Rebellion against an anti-clerical national regime, Pope Benedict recited the invocation that served as the Cristeros' rallying cry: "Long live Christ the King and Mary of Guadalupe."
But reaffirming his message of nonviolence, the Pope prayed that Mary's influence would "promote fraternity, setting aside futile acts of revenge and banishing all divisive hatred."
The presidential candidates from Mexico's three main political parties attended the Mass, along with President Felipe Calderon and his family.
The Vatican said 640,000 people attended the Mass. Some Mexicans took long trips just to see Pope Benedict on his first trip to the country since being elected in 2005.
The journey was not easy for many. Thousands of the faithful walked more than three miles from parking lots in the town of Silao, 220 miles northwest of Mexico City.
"This is nothing too difficult," quipped Jose Trinidad Borja, 81, a retired hardware store owner from Queretaro who boasts of having participated in the annual eight-day diocesan pilgrimage to the Basilica of Guadalupe in Mexico City for 65 straight years.
An army of vendors hawked water, coffee and tamales along the route in addition to Vatican flags and photos of Pope Benedict and his predecessor, Blessed John Paul II, who, with his five visits, became one of the most beloved figures in an officially secular country.
"With Benedict, I feel something indescribable," said Guadalupe Nambo Gutierrez, a retired secretary from Guanajuato City, who saw the Pope in the colonial town March 24 and attended the Mass the following day.
Getting a ticket was another matter. Nambo won a raffle for some of the tickets the Archdiocese of Leon allotted to St. Joseph and St. James the Apostle Parish. Others simply decided to try their luck by showing up -- and many could be seen outside the Mass site behind barricades guarded by federal police officers.
Bishop Raul Vera Lopez of Saltillo said his diocese only received its allotment of 2,500 tickets 10 days before the Mass, making it difficult for parishes to plan trips for churchgoers. Still, all the tickets were claimed and more than 6,500 requests were made.
Most of those coming from Saltillo, in northern Mexico, traveled overnight and were expected to return immediately after the Mass. Some parishes opted not to send people to the Mass because of concerns about security along the route.
"We hope that things calm a little after this visit," said Silao resident Jorge Morales as he walked to the Mass.
The previous evening, after a brief appearance before a crowd in Guanajuato's main square, Pope Benedict privately greeted a group that included eight people who have lost relatives to violence, much of it drug-related, which has killed nearly 50,000 Mexicans over the last five years.
Addressing his remarks there particularly to local children, the Pope called on "everyone to protect and care for children, so that nothing may extinguish their smile, but that they may live in peace and look to the future with confidence."
On several previous international trips, Pope Benedict has met with local victims of clerical sex abuse, but no such meeting has been announced for this visit.
On March 24, sex abuse victims of the late Father Marcial Maciel Degollado, founder of the Legionaries of Christ, held a press conference to present a new book criticizing the Vatican's failure to act against Father Maciel, whom Pope Benedict eventually disciplined and posthumously repudiated.