God dwells on high, yet He becomes a child and puts Himself in the state of complete dependence typical of a newborn child. Nothing can be more sublime, nothing greater than the love which thus stoops down, descends, becomes dependent.
Saint Luke's account of the Christmas story tells us that God first raised the veil of His hiddenness to people of very lowly status, people who were looked down upon by society at large - to shepherds looking after their flocks in the fields around Bethlehem. Luke tells us that they were 'keeping watch'.
This phrase reminds us of a central theme of Jesus's message, which insistently bids us to keep watch, even to the Agony in the Garden - the command to stay awake, to recognise the Lord's coming, and to be prepared.
To a watchful heart, the news of great joy can be proclaimed: for you this night the Saviour is born. Only a watchful heart is able to believe the message. Only a watchful heart can instil the courage to set out to find God in the form of a baby in a stable. Let us now ask the Lord to help us, too, to become a 'watchful' people.
With these thoughts, we draw near to the Child of Bethlehem - to the God who for our sake chose to become a child. In every child we see something of the Child of Bethlehem. Every child asks for our love.
Let us think especially of those children who are denied the love of their parents. Let us think of those street children who do not have the blessing of a family home, of those children who are brutally exploited as soldiers and made instruments of violence, instead of messengers of reconciliation and peace.
The Child of Bethlehem summons us once again to do everything in our power to put an end to the suffering of these children; to do everything possible to make the light of Bethlehem touch the heart of every man and woman.
Only if people change will the world change; and in order to change, people need the light that comes from God, the light which so unexpectedly entered into our night.
These are extracts from Benedict XVI's 2008 Christmas homily in St Peter's Basilica.