Mexico church divided over drug wars
The street vendors outside the iconic Basilica de Guadalupe in Mexico City are doing a roaring trade.
Everything from incense and candles to huge portraits of the Pope are flying off the shelves. Unfortunately for Benedict XVI, they are pictures of his predecessor, John Paul II - a man still held in great affection by Mexicans.
The Pope's Mexico visit is part of his inaugural Latin America tour.
Mexico has the largest Roman Catholic community in this part of the world.
Inside the cool of the cathedral, the priest compares the street sellers with the moneylenders in the New Testament that Jesus drove from the Temple.
But critics say that, in these troubled times in Mexico, it is the hierarchy of the Church itself which has failed to live up to the teachings of the Bible.
Some 50,000 people have been killed in drug-related violence since 2006 and the Church has been accused of failing to speak out over the fighting.
Drugs money cloud
"The Church has had an ambivalent response to the drug war and the incredible amount of violence going on in the country," says John Ackerman, Professor of Law at the Autonomous University in Mexico City.
Since the Christian Democrats came to power in 2000, the constitutionally separate relationship between the Catholic Church and the government has been progressively narrowing.
"This all started during the Fox administration when Vicente Fox kissed the Pope's ring when he came to Mexico," recalls Professor Ackerman.
"It was totally unprecedented and was seen as a major transformation, at least symbolically, in terms of the separation between Church and state."
He says Pope Benedict will find in Mexico a clergy deeply divided over its position on the fighting.
"The general impression is that those Church leaders who have spoken out against violence and in favour of a change in policy have all been relatively low-level leaders. The one exception is Bishop Raul Vera," says Professor Ackerman.
Bishop Vera is a silver-haired, balding priest who is quick to laughter, but equally quick to criticise.
When the BBC caught up with him in a small airless office in Mexico City's airport, as he was returning to his dioceses of Saltillo in the conflict-ravaged north, he certainly was not pulling any punches.
"The president's war against drug trafficking seems to us to be more of a war against the people than a war against the cartels," he says, stabbing his finger in the air.
"The cartels have multiplied, the number of dead has risen exponentially, corruption is deeper every day - we see it. So when we hear the president of the Republic saying his strategy is working, we think he's either in an ivory tower and has no idea what's actually going on, or basically he's a liar. I'm going with the latter!"
But his anger is not just reserved for the state. He is equally critical of some of his colleagues in the Catholic Church.
One of the most serious charges against the Church is that there are some parishes that have actually profited from the drug violence in the form of donations from drug barons or cartels.
"We have to be very careful about who we accept donations from, particularly to fund structures of the Church. Very careful indeed," says Bishop Vera.
It is alleged that drug money has swelled the coffers in parishes where the drug lords exert control.
"There was once a rather embarrassing bishop who said something absurd," remembers Bishop Vera. "He said that money from drug trafficking was purified when it entered the Church. Of course it's not! The money from drugs is intrinsically stained with blood and we can't use it. We mustn't."
One such church can be found in the town of Pachucha, in the state of Hidalgo. Its bright orange façade and gleaming stainless steel cross on the roof stand out among the rudimentary brick housing of the neighbourhood.
On a hill overlooking the church is a mansion, allegedly the home of Heriberto Lazcano Lazcano, the man who paid for the chapel and who the authorities say is the head of the feared and brutal drugs gang, Los Zetas.
There was even a plaque on the wall until very recently dedicated to Heriberto Lazcano Lazcano, and every year at local fiestas a floral arrangement hangs from the church door thanking the Lazcano family.
For many, this chapel is a symbol of an unholy alliance which has sprung up between the Church and the drug cartels in some parts of Mexico.
But for every parish priest who has accepted, willingly or otherwise, a donation from the cartels, there is someone like Angela Casas Mendez - a nun working in the true traditions of Liberation Theology in Latin America.
"We are all part of this spiral of violence," says the small, forceful woman, who runs peace-building social projects in some of the most dangerous areas of Mexico.
"It's not about blame, nor saying 'it's the government's job' or 'this is the Church's responsibility'. We shouldn't say 'those are the bad people, and we are the good ones'."
Sister Casas Mendez has been holding workshops with priests and nuns from Colombia to share experiences about pastoral care in conflict zones, and she says she and her colleagues have been targeted by the drug gangs in the past.
Father Oscar Arias, of the Catholic Church's official charity Caritas, says that the criticisms against the church are politically motivated.
"We are around 6,000 priests working all over the country every day to build peace and construct another society," he says.
"We work in those difficult places with courage and our faith in our God. And the priests stay there, every day, helping families and the communities, despite the violence that they are facing."
When Pope Benedict arrives in Mexico, he will find a complex picture awaiting him. There are those who fear that his visit is primarily political, coming just days before the official start of campaigning in the country's presidential election.
But for the faithful who turn up at the Basilica in Mexico City every week to give thanks to the Virgin de Guadalupe, they are simply hoping to hear an unequivocal message of peace and reconciliation from the Pontiff.