"In his miraculous birth, Jesus was the fruit of heaven and earth ... He was conceived of the Holy Spirit, born of the Virgin Mary. That is the way Jesus is always conceived. That is the way he is reproduced in souls. He is always the fruit of heaven and earth."
These remarkable words open the classic work on the Holy Spirit, The Sanctifier. Archbishop Martinez, the former Archbishop of Mexico.
Sanctification requires our cooperation
When God became man, he did it with the full, free cooperation of Mary, his Blessed Mother. When God sanctifies us, it is also with the full and free cooperation of Our Lady. The Holy Spirit is the Sanctifier from the Latin sancta facere - to make holy. But we are not merely passive in the work of our sanctification. As St. Augustine said, "God who created you without you, will not save you without you." And Mary's role is even more indispensable than our own, because she wants our sanctification even more than we ourselves do.
God Himself came to visit the world. And not just to visit, but to save us. He could have come by becoming a grown man, without a mother. However, He chose a different manner of coming: by being conceived in a Mary's virginal womb, born a subject of the law to redeem the subjects of the law. God works through human actions and circumstances. In His loving providence, God can make use of anything. In the Incarnation of Jesus Christ, Mary was the willing instrument in God's divine plan.
Our sanctification and Mary's cooperation
Our Lady was chosen, prepared and sanctified from her first moment of life to be the Mother of Christ. She was also chosen to be the mother of Christ's body, the Church. She works with the Holy Spirit in the continual presence of Christ throughout the centuries. Every virtue, every true prayer, every supernatural act of forgiveness or charity or humility comes from grace, moved by the Holy Spirit and mediated by Mary to the mystical body of Christ.
"The love of God is poured in our hearts through the Holy Spirit who is given to us" (Rom 5:5).
When grace is poured into the soul through baptism, the Holy Spirit - God Himself - becomes the soul's delightful guest. And this Divine Guest is not idle. He works in us through love.
Our Lady does not dwell in our souls in this way, but she cooperates freely and fully in our sanctification. Through her intercession, she prepares our souls to be fitting places for her Divine Spouse, the Holy Spirit, to dwell in our hearts. Our Lady gave birth to Jesus Christ 2000 years ago but her role in salvation didn't end there. She continues to be intercessor, model of all virtue and grace, mother of divine grace. That is why we ask her to pray for us now and when we are dying, so that we will more closely be conformed to Her Son in this life and live in union with Him in the next.
God became man through the Holy Spirit, but only with the consent of Mary who, moved by grace, generously and completely surrendered her body and soul for God's plan of salvation. When we are elevated to divine grace, it is once again through the Holy Spirit, and only with the consent of Mary for God's plan of sanctification.
Author's note: Many ideas from this article have come from The Sanctifier by Archbishop Luis M. Martinez. If you wish to look more deeply into the role of the Holy Spirit and Our Lady in our sanctification, I'd highly recommend this classic work on the Holy Spirit.