The Most Rev Justin Welby told worshippers at Canterbury Cathedral that the "language of love" is spoken by God "for the poor and suffering and oppressed in every place at every time".
He said the world does not stop because it is Christmas.
"To think so is a dangerous illusion because God came into the reality of the world, to change it, not to give us an escape from it," he said.
The archbishop told the congregation: "God's language of love is exclusive. It requires us to forget other languages of hatred, tribalism, rivalry, political advantage and of materialism, pride, greed, and so many more.
"God's language of love is not mushy sentiment. In the Bible we see the richness of its vocabulary.
"It encompasses every aspect of living, and every aspect of knowing God. Jesus the adult spoke it perfectly.
"The baby in the manger lives it flawlessly before he can speak a word, because by his mere existence he is the word of God to us.
"It can be spoken by the generous and wealthy and powerful."
The sermon came after thoughts of peace, joy and sadness were raised in the Christmas messages of the Bishops of the Church of England.
The bishops spoke of modern-day challenges from modern slavery to political divisions and urged people to remember those who struggle with Christmas as a lonely or difficult time of year.
Graham Usher, the Bishop of Dudley, recalled a recent visit to Bethlehem but also thought of divisions that are closer to home.
He said: "Our current political debates also put up barriers between those who voted in different ways. Our country needs, more than ever, to seek grace and generosity in our political conversation so that there are not winners and losers, just the flourishing of all."
Delivering a sermon at York Minster, the Archbishop of York, Dr John Sentamu, said: "Even in uncertain times – like Brexit for us all – the hope is still there, the belief that into darkness God can still shine a light."