The annual "Urbi et Orbi" message, "To the city (of Rome) and to the world," pointed out peace is not merely a balance of opposing forces, but "calls for daily commitment... wars shatter and hurt so many lives."
The message, delivered before an audience estimated by Vatican TV of 150,000, concentrated on prayer for innocents caught in political conflict.
The Pope, 77, called for prayer to "ask the Lord to spare the beloved Syrian people further suffering and to enable the parties in conflict to put an end to all violence, and guarantee access to humanitarian aid."
The message also made reference to violence in Iraq, South Sudan, Nigeria, the Central African Republic, the Democratic Republic of Congo and the Horn of Africa.
He ended saying: "God is peace. Let us ask him to help us to be peacemakers each day, in our life, in our families, in our cities and nations. Let us allow ourselves to me moved by God's goodness."
The large turnout reflected the popularity Pope Francis has enjoyed since becoming head of the Catholic Church, CNN said, noting his down-to-earth manner has touched a chord with millions.
There were a record number of requests to attend his Christmas Eve Mass at St. Peter's Basilica, the Vatican said.
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