Pope Benedict strengthens his call for all people of good will to work to build up a marriage culture:
"Pope Benedict XVI has suggested that attempts to give gay unions the same status as marriages between men and women pose a threat to justice and peace.
"There is also a need to acknowledge and promote the natural structure of marriage as the union of a man and a woman in the face of attempts to make it juridically equivalent to radically different types of union," the pope said in his message for World Day of Peace 2013, which was presented by the Holy See on Friday.
"Such attempts actually harm and help to destabilize marriage, obscuring its specific nature and its indispensable role in society.
"These principles are not truths of faith, nor are they simply a corollary of the right to religious freedom.
"They are inscribed in human nature itself, accessible to reason and thus common to all humanity.
"The Church's efforts to promote them are not therefore confessional in character, but addressed to all people, whatever their religious affiliation.
"Efforts of this kind are all the more necessary the more these principles are denied or misunderstood, since this constitutes an offence against the truth of the human person, with serious harm to justice and peace".
The pope's message for World Day of Peace 2013, which takes place January 1, is entitled Blessed are the Peacemakers."