VATICAN CITY (AP) -- The Christmas season kicked off Friday at the Vatican with the traditional lighting of the tree in St. Peter's Square -- and a reminder from the pope about what happened when the "lights" of God were turned off in past atheistic regimes.
Benedict XVI, 85, occasionally refers to his experiences as a devout young Catholic in Nazi Germany in pressing his case for Europe to recover its Christian heritage and reassert its faith in everyday life.
In comments to a delegation from Italy's south-central Molise region, which donated the Vatican's main Christmas tree this year, Benedict said the tree lights that were being turned on at a ceremony early Friday evening represented "divine light."
"And when in the past they tried to stamp out the light of God to instead turn on illusory and misleading glows, there were seasons of tragic violence against man," he said.
"And this is because when they tried to cancel God's name from the pages of history, the result was a distortion, where even the most noble and beautiful words, like 'freedom,' 'common good' and 'justice' ... lost their true meaning."
When the tree was lit, singers from the Molise area sang traditional local songs, and a Vatican band played Christmas melodies.
Friday marked the start of a busy Christmas season for Benedict that will culminate with Mass on Christmas Eve in St. Peter's Basilica, a speech on Christmas Day and another Mass on New Year's Day to mark the Catholic Church's world day of peace.
The Vatican on Friday released the pope's peace message, in which he called for policymakers to think of themselves as peacemakers in economic and social policy. He warned that abortion and gay marriage were threats to peace.
"Those who insufficiently value human life, and in consequence, support among other things the liberalization of abortion perhaps do not realize that in this way they are proposing the pursuit of a false peace," since peace presupposes protecting the weakest, he wrote.
Laws granting legal status for gay unions, he said, "actually harm and help destabilize marriage" by obscuring its specific nature as a union between man and woman that forms the basis of society.
Benedict also renewed his call for a new world financial order guided by ethical and moral decisions, saying the profit-at-all-cost mentality of the past was selfish and destructive.
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