The Pope made this reflection today during his address before praying the midday Angelus with those gathered in St. Peter's Square.
He suggested two aspects to learn from Mary, as a guide to preparing for Christmas.
The first is her "'here I am' full of faith."
"Mary does not know which paths she will have to trod, which sorrows she will have to suffer, which risks she will face," the Pontiff said. "But she knows that it is the Lord who is asking, and she trusts totally in Him and abandons herself to His love. This is Mary's faith."
The other aspect to learn from "this simple young woman of Nazareth," the Pope said, is her ability to "recognize the time of God."
She makes the Incarnation possible, "thanks to her humble and courageous 'yes,'" the Pope said. "Mary teaches us to welcome the favorable moment in which Jesus comes into our lives and asks for a generous and prepared response."
Jesus is coming this Christmas in the "today of the liturgy," the Pope explained. "The Word, who dwelled in the virginal womb of Mary, in the celebration of Christmas, comes to call anew the heart of each Christian. He comes by and calls. Each one of us is called to respond, as Mary did, with a personal and sincere 'yes,' placing ourselves fully at the disposal of God and his mercy."
"How many times Jesus comes in our lives and how many times he sends us an angel. And how many times we don't realize it because we are very busy, submerged in our thoughts, in our activities, and in these days, in the preparation for Christmas, and we don't realize the one who is passing by and knocking at the door of our hearts asking to be welcomed, asking for a 'yes' like that of Mary."
The Pope said that when we feel in our hearts a desire to be better, to repent, that the Lord is the source of that feeling.
"If you feel this, stop," he said. "The Lord is there. Go to pray, and maybe go to confession to clean up the dwelling a bit. This is good. But remember well, if you feel this desire to improve, it is He who is calling. Do not let him pass by."
Pope Francis concluded by inviting the faithful to learn from Mary's and Joseph's example, and to "welcome Jesus with an entirely open soul."
Jesus, he said, "comes to bring to the world the gift of peace. [...] The precious gift of Christmas is peace and Christ is our true peace. And Christ calls to our hearts to give us peace. Peace of the soul. Let us open the gates to Christ."