Pope Francis used his homily to again highlight the dangers of the commercialisation of Christmas marking out the similarities between the housing crisis facing Mary and Joseph and the prevailing attitude at Christmas today.
"The mystery of Christmas, which is light and joy, questions and unsettles us, because it is at once both a mystery of hope and of sadness. It bears within itself the taste of sadness, inasmuch as love is not received, and life discarded," Pope Francis said.
"This happened to Joseph and Mary, who found the doors closed, and placed Jesus in a manger, 'because there was no place for them in the inn' (v. 7). Jesus was born rejected by some and regarded by many others with indifference.
"Today also the same indifference can exist, when Christmas becomes a feast where the protagonists are ourselves, rather than Jesus; when the lights of commerce cast the light of God into the shadows; when we are concerned for gifts but cold towards those who are marginalized."
Security measures had been beefed up in Rome and around the Vatican before and after the mass at St Peter's Basilica after Italian police killed the man believed to be responsible for the Berlin market truck attack.
Francis added though that the general message of the nativity remains one of hope.
"Yet Christmas has essentially a flavour of hope because, notwithstanding the darker aspects of our lives, God’s light shines out," he told the approximately 10,000 worshippers gathered to celebrate the start of Christmas.
"His gentle light does not make us fear; God who is in love with us, draws us to himself with his tenderness, born poor and fragile among us, as one of us. He is born in Bethlehem, which means “house of bread”. In this way he seems to tell us that he is born as bread for us; he enters life to give us his life; he comes into our world to give us his love.
"He does not come to devour or to command but to nourish and to serve. Thus there is a direct thread joining the manger and the cross, where Jesus will become bread that is broken: it is the direct thread of love which is given and which saves us, which brings light to our lives, and peace to our hearts.