What is Saint John Duns Scotus’ title of glory?

The Eastern Churches have always celebrated the original purity of Mary in a feast of the "Conception of the Holy Mother of God," or, more exactly, the feast of Mary's conception in the womb of Saint Anne.

The Latin Church adopted it gradually during the 10^th century, but St Bernard, St Bonaventure, and St Thomas Aquinas still refused to admit this "immaculate conception." Saint John Duns Scotus was the first to make it triumph and to get the Sorbonne of Paris to rally around this doctrine. The Popes intervened many times over the centuries to silence this quarrel until the day when Pius IX defined it as a dogma of faith in 1854:

"From the first moment of her conception, through the unique grace and privilege of Almighty God, the Blessed Virgin Mary was preserved from original sin. As on the first day of Creation when Adam and Eve came out of the hands of the Creator, the mother of his Son was there, a tiny human cell endowed with a holy soul, and thus she became the glory of our sinful nature. "

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