Pope Francis unveiled the figurine of a newly-born Jesus and kissed its knee, before beginning the Mass on Christmas eve at St. Peter's Basilica.
"Through the course of history, the light that shatters the darkness reveals to us that God is Father and that his patient fidelity is stronger than darkness and corruption," he said during his homily.
At the end of the Mass, he carried the figurine of Jesus down the main aisle and then handed it to a priest who placed it in the Nativity scene inside the basilica.
Earlier on Wednesday evening, Francis urged Christian refugees in a camp in Irbil in northern Iraq to stay strong, during a phone call arranged by TV2000, the television of the Italian bishops' conference.
"You're like Jesus on this night, and I bless you and am close to you," Francis told the Iraqis, according to the audio of the call.