The Solemnity of the Immaculate Conception of Mary commemorates an action of God deeply linked to Christmas, a celebration for which we are preparing. Today we celebrate God’s special intervention, together with the Son of God, at the moment when the Virgin Mary was conceived in the womb of her mother, St. Anne. While all human beings are conceived and born in need of God’s salvation, subject to the law of death and inclined to sin, Mary was saved from the very moment of her conception.
Unlike us, who are born with original sin, the Virgin Mary was preserved from this lack. Her conception was immaculate, free from sin. She was saved beforehand by Christ so that the Son of God could be born from a pure and holy root. Thus, being conceived without original sin, Mary became, by divine grace and favor, the pure and holy beginning of a history of salvation that would culminate in the incarnation of the Son of God in her womb. God thus prepared the one who would become his Mother.
Mary became the pure and holy beginning of a history of salvation that would culminate in the incarnation of the Son of God in her womb.
The foundation of this faith lies, in the first place, in the conviction that the Son of God could not be born of a woman affected by sin. God and sin are incompatible. Although the Son of God was born into a world of sinners and came to save us, he himself was free from sin. 
This idea, that the human origins of the Savior should be clean of sin, led to the certainty that his mother should be holy from her roots. This conviction finds its foundation in the words of the angel Gabriel when he greets Mary and calls her “full of grace”. This term means that Mary was especially favored by God, chosen for a unique mission. This favor did not begin with the angel’s visit, but goes back to the beginning of her existence, to the moment of her conception in the womb of St. Anne, when God preserved her from sin and death. While we are purified from sin by baptism, the Virgin Mary was not purified, but preserved from all sin from the first moment of her life. In short, we celebrate that God is greater, purer and more powerful than human sin.
“Let us sing to the Lord a new song, for he has done wonders.”
Today we have repeated the refrain: “Let us sing to the Lord a new song, for he has done wonders”. These wonders are reflected in the Virgin Mary, but also in the whole plan of salvation that God has designed for our good. Mary’s immaculate conception was intended to prepare for the incarnation of the Savior of us all. The words of St. Paul in his letter to the Ephesians, which we have read today, teach us that we too have been in God’s mind since the creation of the world: “Blessed be God, the Father of our Lord Jesus Christ, who has blessed us in him with every spiritual and heavenly good thing. He chose us in Christ, before he created the world”. This divine election includes both the Virgin Mary, by her immaculate conception, and all of us, through the gift of faith, baptism and the sacraments. God chose us to be holy and blameless in his eyes, out of love. Mary was holy and blameless from her conception; we, through listening to the Word, baptism and perseverance in good works.
If human history is marked by sin since the disobedience of Adam and Eve, the history of holiness is marked by grace,
God’s saving purpose is realized in us through faith, baptism, charity and the Eucharist, as well as through perseverance in good works and hope. God has made us his children and, together with Christ, has constituted us heirs of eternal life. He has enabled us to share in his divine life through the Holy Spirit. For this we were created: to participate in the root of holiness that was introduced into the world with Mary’s immaculate conception, uniting us to Christ through faith, the sacraments and good works.
In today’s first reading, we recalled what happened after Adam and Eve’s sin, when they hid from God. He came down to the garden and asked, “Where are you?” Since then, God continues to come down to the world to call us and tell us, “Where are you? Do not hide from me. If you are ashamed because you have sinned, do not hide, for only if you acknowledge your sin can I heal you.” This question of God became clearer and more urgent with the sending of his Son, who came to seek out sinners, offer them forgiveness and integrate them into the history of holiness that began with Mary’s immaculate conception. If human history is marked by sin since the disobedience of Adam and Eve, the history of holiness is marked by grace, whose origin is in the death and resurrection of Christ, born of Mary’s holy root. Let us rejoice and thank God for his infinite goodness.