Things are no longer what God says, Manuel and María now believe. In their 80s, the couple were married in a Catholic church sometime in the 1950s and baptized their three children. Two of their children were also married by priests, but the third one only had a civil wedding. Three of their two grandchildren made their first communions. But the only ones who regularly attend Sunday Mass are Manuel and María. "That's how much times have changed," says the grandmother.

The times are indeed changing for a society that once identified itself as staunchly Catholic. Although Catholicism is the most predominant religion in Spain, the numbers of those who openly declare themselves as Catholic are dropping. A recent poll taken by the state-run Center for Sociological Investigations (CIS) shows that 71.7 percent of people in Spain say they are Catholic - a nearly 10-point drop from 82.1 percent in 2001.

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One out of four Spaniards says they are either atheists or non-believers.

"The only people you see at church these days are elderly people and maybe some children. You hardly see anyone from other generations," says María, as she recalled the flocks that once filled the pews at Sunday midday Mass years ago.

The CIS poll supports María's observation: the number of Catholics drops as age groups get younger. Nine out of 10 people over 65 say they are Catholic but only half that ratio say they are believers in the 18-24 age group.

"Spanish society is gradually becoming more secular, which is worrisome," says Father Jesús de las Heras, editor of the magazine Ecclesia, which is published by the Episcopal Conference. "The causes of secularization are various and complex. In part, society has forgotten what lies beyond. And with economic development, material goods have become a substitute for spirituality, and this has suffocated people's faith," De las Heras said.

Sometimes Manuel and María want to ask their children and grandchildren what has happened to their religious upbringing, but they don't dare bring it up during their traditional Sunday lunches when the entire family gets together. Religion is a private matter, and the only time grace is said at the table is before Christmas Eve dinner.

Episcopal Conference officials declined to speak with EL PAÍS about the poll.

But Javier Baeza, a priest at a church in one of Madrid's rougher neighborhoods and who is involved in the 15-M movement, sees it differently. "Religious indifference in general can be blamed on the tradition of a religious culture that is accusatory because of sin and human wickedness. In general, people believe in God, but they have rejected the [Catholic Church] hierarchy."