Pope Benedict XVI has expressed concern about the increasing commercialisation of Christmas as he conducted the Christmas eve mass, urging the faithful to look beyond the holiday's "superficial glitter" to discover its true meaning.

"Today Christmas has become a commercial celebration whose bright lights hide the mystery of God's humility, which in turn calls us to humility and simplicity," the Pontiff said while presiding over the service at St. Peter's Basilica.

Benedict, 84, will be visiting different places as part of Christmas celebrations in the next two weeks, which might strain his already fragile health.

The Christmas eve mass was rescheduled to 10 p.m. from midnight years ago to allow the Pope to avoid late night mass.

"Let us ask the Lord to help us see through the superficial glitter of this season, and to discover behind it the child in the stable in Bethlehem, so as to find true joy and true light," he said.

The Pope prayed for those "in poverty, in suffering, as migrants, that a ray of God's kindness may shine upon them, that they and we may be touched by the kindness that God chose to bring into the world."

"At this hour when the world is continually threatened by violence in so many places and in so many different ways, when over and over again there are oppressors' rods and bloodstained cloaks, we cry out to the Lord," the Pope said while expressing concern over the rising incidents of violence across the world.

The Pontiff lighted a candle as a sign of peace, as thousands of pilgrims and tourists gathered to witness celebrations at the Vatican city.

He will deliver his traditional Latin "Urbi et Orbi" speech, which means for "to the city and the world," on Christmas day from the central loggia of St. Peter's overlooking the piazza. The speech usually touches upon the hardships and wars confronting humanity. He will also deliver Christmas greetings in several languages.

Pope Benedict XVIPress Association
Pope Benedict XVI delivers his blessing as he leaves after celebrating Christmas Mass in St. Peter's Basilica at the Vatican on 24 December.Press Association
Pope Benedict XVI kneels as he leads the Christmas mass in Saint Peter's Basilica at the Vatican.Reuters
People line up to take part at Christmas mass led by Pope Benedict XVI in Saint Peter's Basilica at the Vatican.Reuters
Pope Benedict XVI leaves after celebrating Christmas Mass in St. Peter's Basilica at the Vatican on December 24.Press Association