(Please note that the Solemnity of the Immaculate Conception in 2019 is transferred to Monday, December 9th, this year and is not a holy day of obligation.)
A feast called the Conception of Mary arose in the Eastern Church in the seventh century. It came to the West in the eighth century. In the 11th century it received its present name, the Immaculate Conception. In the 18th century it became a feast of the universal Church. It is now recognized as a solemnity.
In 1854, Pius IX solemnly proclaimed: “The most Blessed Virgin Mary, in the first instant of her conception, by a singular grace and privilege granted by almighty God, in view of the merits of Jesus Christ, the savior of the human race, was preserved free from all stain of original sin.”
It took a long time for this doctrine to develop. Many Fathers and Doctors of the Church considered Mary the greatest and holiest of the saints. Two Franciscans, William of Ware and Blessed John Duns Scotus, helped develop Marian Theology. They pointed out that Mary’s Immaculate Conception enhances Jesus’ redemptive work. Other members of the human race are cleansed from original sin after birth. In Mary, Jesus’ work was so powerful as to prevent original sin at the outset.
In Luke 1:28 the angel Gabriel, speaking on God’s behalf, addresses Mary as “full of grace” or “highly favored”. In that context, this phrase means that Mary is receiving all the special divine help necessary for the task ahead. However, the Church grows in understanding with the help of the Holy Spirit. The Spirit led the Church, especially non-theologians, to the insight that Mary had to be the most perfect work of God next to the Incarnation. Or rather, Mary’s intimate association with the Incarnation called for the special involvement of God in Mary’s whole life.
The logic of piety helped God’s people to understand that Mary was full of grace and free of sin from the first moment of her existence. Moreover, this great privilege of Mary is the highlight of all that God has done in Jesus. Rightly understood, the incomparable holiness of Mary shows forth the incomparable goodness of God.