How the Dogma of the Immaculate Conception Was Defined

Divinely revealed truths do not change.

But sometimes it takes a while to figure out what those truths are.

It took the Church hundreds of years before it finally settled the question of who exactly Jesus Christ was in the most basic terms of the question—God? Man? One person or two? (The Council of Chalcedon, in 451, hashed out what has been the Church’s final answer.) It also took hundreds of years before the Church affirmed, in a dogmatic definition, the divinity of the Holy Spirit (Council of Constantinople, 381).

Then there is the definition of the dogma of the Immaculate Conception. That took nearly two millennia. Or, 1854 years after the birth of Christ to be exact.

The Church had always believed in the sinlessness of Mary. Justin Martyr and Irenaeus identified Mary as a second Eve, as one who undid Eve’s work in bringing humanity into sin. Origen, one of the earliest Church Fathers called her “immaculate of the immaculate.” St. Augustine did not even want to raise the question of sin in Mary out of honor for her Son.

The dogma was implied, but not defined in their statements. While venerating Mary, the Church had stopped short of the absolutism required by the dogma of the Immaculate Conception—which holds that Mary was spared even the stain of original sin at the moment of her conception—because it also did not want to go so far as to say that Mary was not in need of Christ her savior. That certainly seemed very wrong.

The solution eluded some of the brightest minds and greatest saints of Christendom. In the Summa Theologica, St. Thomas Aquinas affirms only that Mary was sanctified in the womb and that the inclination to sin caused by original sin was fettered in her person. St. Bernard of Clairvaux believed that Mary could have been sanctified soon after the moment of conception, but not at her conception.

Instead, it took an obscure monk, a Franciscan dunce, and a French nun to help win the Church over to acceptance of this dogma.

The turning point undoubtedly was the work of the great Franciscan scholastic theologian, John Duns Scotus, who lived and worked from the late 1200s early into the next century.

But much of the intellectual heavy lifting was done well over a century before him by an English Benedictine monk named Eadmer. Born around 1060, Eadmer became a close companion and biographer to St. Anselm of Canterbury. (Eadmer is even sometimes referred to as Pseudo-Anselm.) Eadmer would later write the lives of many other English saints, including Sts. Wilfrid, Oda, and Dunstan.

Eadmer was once offered a position as the bishop of St. Andrews. He refused, writing that “he would not in exchange for all of Scotland deny himself a monk of Canterbury.” (Besides a commitment to the monastic life, there seems to be more than a tinge of Anglo-Saxon nationalism in his decision. For more about Eadmer read his biography from the Oxford Dictionary of National Biography.) It was at this time that Eadmer reached new, previously unachieved heights in the development of Marian theology.

Eadmer assembles a phalanx of arguments in favor of the Immaculate Conception. As one influential synopsis of his writings sums them up this way: “Taking Mary’s relation to other creatures: St. John the Baptist was sanctified from his birth, what then of Mary? Mary enjoys dominion over all other creatures and must not, therefore, be brought down to our level by original sin; God preserved the Angels from sin and Mary is the Queen of Angels.”

Then there is also the parallel with Eve. Mary completely undid the role of Eve and in a superior way (Eve had been mother of all humanity, Mary was Mother of God). There was also the question of how Mary could cooperate in the Incarnation had she been stained by original sin.

It was left to John Duns Scotus, however, to discover the solution to the dilemma Aquinas and others had—how to affirm the sinlessness of Mary without excluding her from the need for a Savior. He argued that Mary was pre-emptively redeemed by Christ. Or, to use his words, Scotus held that Mary was “preserved” from original sin, rather than freed from it. This formula both affirmed her absolute purity in the strongest possible sense while doing nothing to detract from her need for a Redeemer.

In fact, much of the genius of Scotus’ argument is that the Immaculate Conception further adds to Christ’s own dignity as Mediator. In a theological commentary, Scotus put it this way:

For a most perfect mediator exercises the most perfect mediation possible in regard to some person for whom he mediates. Thus Christ exercised a most perfect act of mediation in regard to some person for whom He was Mediator. In regard to no person did He have a more exalted relationship than to Mary. Such, however, would not have been true had He not preserved Her from original sin.

To prove this claim, Scotus goes on to argue that Christ had to have been “the perfect Mediator of at least one person.” That person must have received from Christ the “greatest possible good”—complete preservation from original sin. “It is a greater good to be preserved from evil than to fall into it and afterwards be freed from it,” Scotus wrote. Therefore, it would have been fitting for Christ to preserve Mary from original sin.

The solution ingeniously shifts the Immaculate Conception from being a belief perceived as being in potential antithesis to the redemptive work of Christ to further supporting it. (Click here to read the full excerpt of Scotus’ argument.) The Church was well on its way towards widespread acceptance. As the Catholic Encyclopedia puts it, Scotus had “so solidly and dispelled the objections in a manner so satisfactory, that from that time onward the doctrine prevailed.”

Yet it would be several hundred more years before the Immaculate Conception was dogmatically defined.

Along the way, one extraordinary intervention from heaven helped nudge the Church forward.

It was July 18, 1830 and a French nun from a little village on the Seine River in what was once part of the wine-rich region of Burgundy lay awake praying to St. Vincent de Paul, asking for a vision of the Blessed Virgin Mary. In her hand she was grasping a relic of the saints, cloth from his surplice. On a sudden impulse, she tore it into two and swallowed one half. Gradually she dozed off only to be awoken by a little boy who called out to her three times, beckoning her to come to the chapel.

Here is how her biographer describes what happened next:

Now they were at the chapel. Catherine gasped in astonishment when the heavy door, which must be locked, swung wide at the child’s mere touch. The chapel was ablaze with light! The chandeliers, the candles on the altar, all burned brightly. Why, she thought, it is like a midnight Mass!

St. Catherine Labouré was about to have her first of several visions of Our Lady. In her second, she saw Mary on a globe with rays of light showering downward from her fingers. She was encircled by these words: “O Mary, conceived without sin, pray for us who have recourse to thee.” This image was an M entwined with a cross and the Sacred Heart and Immaculate Heart beneath it. The image is known to us today as the Miraculous Medal.

It would be a mistake to see this vision as the source of the dogmatic definition that would come a quarter of a century later. New revelation had not been given to the faithful. Rather, the truth of a revelation of which the Church had always been conscious but never fully grasped had been confirmed in some special way. (In his introduction to Marian theology, scholar Mark Miravalle says the vision gave “positive encouragement” to Pope Pius IX.)

The dogma of the Immaculate Conception, now a firm fixture of the Church’s theology and devotion, certainly took the long road to widespread acceptance and belief. One is reminded of Christ’s words in Matthew 11:25, “I give praise to you, Father, Lord of heaven and earth, for although you have hidden these things from the wise and the learned you have revealed them to the childlike.”

image: Abraham Sobkowski OFM / Wikimedia Commons

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Stephen Beale is a freelance writer based in Providence, Rhode Island. Raised as an evangelical Protestant, he is a convert to Catholicism. He is a former news editor at and was a correspondent for the New Hampshire Union Leader, where he covered the 2008 presidential primary. He has appeared on Fox News, C-SPAN and the Today Show and his writing has been published in the Washington Times, Providence Journal, the National Catholic Register and on and A native of Topsfield, Massachusetts, he graduated from Brown University in 2004 with a degree in classics and history. His areas of interest include Eastern Christianity, Marian and Eucharistic theology, medieval history, and the saints. He welcomes tips, suggestions, and any other feedback at bealenews at gmail dot com. Follow him on Twitter at

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