Catholic Dogma -- help me on Immaculate Conception


I’m a lifelong Catholic, 69 years. Something on the back burner has started to boil – I understand a dogma to be something that the Church has believed everywhere for all times.

But the Dogma of the Immaculate Conception was proclaimed around 1858. BUT back in the day of St, Thomas Aquinas, a doctor of the church (i think), he did not believe in the immaculate conception of Mary.

Recently I heard a priest dodge the issues by saying that if the Church had proclaimed the dogma, then he would have supposedly accepted it. But, that’s looking at the issue from the wrong direction. Thomas, a doctor of the church, seems to break the rule of a dogma being believed everywhere at all times. As a consequence, this also seems to contradict the infallibility of the Pope who proclaimed that this teaching was everywhere all the time. Yes, it was not a settled issue. In fact, The “dogma” was proclaimed hundreds of years after Duns Scotus proposed it.

Even that seems problematical. Scotus argued that it was necessary for Mary to be sinless for her to be able to give birth to the Messiah. If i ever knew from logic class what this is called, it seems to be an error of logic of some sort. Why was it necessary for Mary to be sinless, even free of original sin?

One basis of such necessity might be scripture – she would have to be sinless perhaps to fulfill some prophecy. However, I can’t seem to put that in focus – what prophecy? So, there seems to be several obstacles, contradictions, inconsistencies, or historical aberrations here. Any help would be appreciated.


St Thomas also had views about abortion that today we would condemn. General opinion does not equal every opinion.


There is a lot of debate over whether Thomas Aquinas did or did not believe in the Immaculate Conception. It’s not a settled issue that he absolutely didn’t believe it.

Regardless of that, on your question about Scriptural prophecy and support for the dogma, here is the Catholic Answers apologist column on that matter.


When the Blessed Virgin Mary appeared to Sister Catherine Labouré in 1830 although widely believed the Immaculate Conception was not a dogma of the Church requiring belief. From this event, Pope Pius IX is said to have been influenced to consult with the Church on it leading to the definition.

Was it necessary? No. Ineffabilis Deus explains: “And indeed it was wholly fitting that so wonderful a mother should be ever resplendent with the glory of most sublime holiness and so completely free from all taint of original sin that she would triumph utterly over the ancient serpent.”

Gen. 3:15 is the main prophetic scripture.

From Ineffabilis Deus

This doctrine so filled the minds and souls of our ancestors in the faith that a singular and truly marvelous style of speech came into vogue among them. They have frequently addressed the Mother of God as immaculate, as immaculate in every respect; innocent, and verily most innocent; spotless, and entirely spotless; holy and removed from every stain of sin; all pure, all stainless, the very model of purity and innocence; more beautiful than beauty, more lovely than loveliness; more holy than holiness, singularly holy and most pure in soul and body; the one who surpassed all integrity and virginity; the only one who has become the dwelling place of all the graces of the most Holy Spirit. God alone excepted, Mary is more excellent than all, and by nature fair and beautiful, and more holy than the Cherubim and Seraphim. To praise her all the tongues of heaven and earth do not suffice.


Hello Otrrl,

Aquinas’s view of the Immaculate Conception always fascinated me. His theological and metaphysical views almost demanded that he agree with the Immaculate Conception. The only reason he (and St. Bonaventure) wrote against it was that it was ‘scientific fact’ that the soul was not imparted to humans until some time within the pregnancy. There was no identifiable human body within the woman and thus there could be no human soul implanted into it because the soul is the form of the body.

Yes, Aquinas and Bonaventure are Doctors of the Church. This, however, does not mean that all of their writings are infallible. Many of the Doctors have been wrong on certain issues. A Doctor of the Church only has to greatly and uniquely contribute to the Deposit of Faith. Aquinas’s primary contributions for which he was made to be a Doctor was not on the Immaculate Conception, but rather the approach to knowledge of God through the intellect (first 50 questions of the Summa Theologiae) and his work with individuation, species, essence and existence. This latter subject was where his title ‘Angelic Doctor’ comes from as he greatly contributed to our understanding of what and who angels are through the examination of these subjects.

Blessed John Duns Scotus is already considered a scholastic doctor (he contributed to the large deposit of scholastic theology) but is not yet an official Doctor of the Church. He must be fully canonized for this to happen. The fact that it was his argument which was quoted in 1854 by Pius IX gives credence to the belief that he may be made an official doctor when his canonization goes through.

As to the fact that Mary must be sinless for her to give birth to the Messiah, you must look back at the original Fall. It was only through the totally free choice of Eve that sin came into the world and humanity Fell. In order to give Mary even the ability to agree to bear Him who would wash this stain away from the world, she needed to be in the same state of sinlessness and initiate a similar, yet inverse, ‘yes’. It is somewhat of a principle of equivalent exchange, not a self-fulfilling proposition or prophesy. Mary’s response could have been just as negative as Eve’s rejection of God’s command. Christ causes the Immaculate Conception in the sense that the Immaculate Conception must happen for it even to be possible that that free ‘yes’ may be given so that He may come into the world.


I think some of your confusion derives from your understanding of dogma. Although many dogmas refer to truths the Church has believed everywhere for all times, there are other dogmas that reflect a development of doctrine over time. The Catholic Encyclopedia defines dogma as: “a truth appertaining to faith or morals, revealed by God, transmitted from the Apostles in the Scriptures or by tradition, and proposed by the Church for the acceptance of the faithful. It might be described briefly as a revealed truth defined by the Church.”

The Immaculate Conception always was a truth revealed by God and transmitted from the Apostles, but in the beginning, this was only known implicitly. As years went by, the Church further developed an understanding of the truths of revelation. Some medieval authors including Aquinas denied the Immaculate Conception because they had difficulty reconciling it with the fact that Mary had to be redeemed. They didn’t see how it was implicitly contained in Scripture yet. But they aren’t guilty of the sin of heresy because the truth they were denying was not to their knowledge divinely revealed, and had not yet been made a dogma.

Later on, doctrinal development continued and theologians came to realize and agree that the Immaculate Conception is genuinely a truth contained in divine revelation. It became accepted by the Church’s ordinary teaching office and the universal Church came to regard it as a divinely revealed truth. At this stage, denial of it would have been a serious matter, but the teaching was still not a dogma.

It at last became a dogma in 1854 when Pope Pius IX defined it as such in the following words:

“We declare, pronounce, and define that the doctrine which holds that the most Blessed Virgin Mary, in the first instance 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, is a doctrine revealed by God and therefore to be believed firmly and constantly by all the faithful.”





Here is a link to the Catholic Answers article about it.

The Immaculate Conception and Assumption

Have you read this book? It’s very helpful in explaining all the doctrines concerning Mary.


I was really hoping Fr. Mike would be singing a narrative song about it based on the guitar shown on the opening frame


He plays and sings Mary, Did You Know? at the end though! :grin:


Something being believed always and everywhere is one of the ways for a doctrine to be infallible. Explicit definitive pronouncement by the Pope is a separate way.

Also, Aquinas’s disagreement with Immaculate Conception was very technical, there was no dispute about Mary being sinless.


This is incorrect. Aquinas never at any time disputed that abortion is always and everywhere wrong.


Sometimes I need a direct quotation in order to know what Aquinas actually said and his reasons for doing so.


Yah I have serious issues understanding both the Immaculate Conception and also the Assumption of Mary which is also a quite recent dogma.
My issue like you has to do with Thomas Aquinas, and also the Churchs reasoning for it seemed to be inspired more by the apparition at Lourdes than anything. Also, the Eastern Orthodox, although in schism , were part of the Church for over a millennium. If so why don’t they believe in it since they also should have always believed in it if we do.
I tell you I accept the Church in what it teaches, but those two are really hard for me to understand. I have no idea where the information comes from. There’s some apocryphal New Testament books that give the Immaculate Conception and the Assumption validity, however the Church chose not to include them in scripture so using those as sources seems strange, almost like, well yah why aren’t they in the Bible then. I know for example Mary’s parents names come from the Proevangelium of Mary. The Birth of Mary seems to back up the Immaculate Conception. I forgot which one backs up the Assumption but one book does describe Mary dying and the Apostles not being able to find her body. These are all non canonical texts however.
So really there is no Biblical evidence nor Tradition evidence as like you said Church doctors questioned it right up to the 13 century at least.


Here’s a pertinent quote from a Catholic scholar.

The doctrine of the Immaculate Conception [unlike the Bodily Assumption], was raised as a question about the year 1100, and was not settled until 750 years later. (Edward O’Connor, “Preface” in The Dogma of the Immaculate Conception, ed. Edward D. O’Connor [Indiana: University of Notre Dame Press, 1958, 2016] vi; comment in square bracket added)

Also, the text of the revelation of Mary to St, Bridget says the following:

Know that my Conception has not been known to all, for God so willed it, that as the natural law and the voluntary election of good and evil preceded the written law, and afterwards came the written law, which restrained every inordinate emotion; so has it pleased God that even my friends should have pious doubts concerning my Conception, and that each should display his zeal, until at the preordained time the truth shall shine forth” (Book vi, 55). (William Bernard Ullathorne, The Immaculate Conception of the Mother of God [Westminster, UK: Art and Book Company, 1904], 157)

So, this doesn’t seem to be a teaching that can be traced back to the Apostles.


That song is very non Catholic. It annoys me when I hear it played at Catholic Churches. By the Church, yes Mary knew. It isn’t a question. That song if taking the lyrics to literal borders on heresy.


When the angel came to Mary, he greeted her by saying “Hail Mary full of grace” She was full of grace because she was immaculately conceived.


The Orthodox and Eastern Catholics definitely do have a similar teaching, though not identical, to the Assumption. It is an ancient teaching. In the Eastern Rite world it is known as the Dormition.

So, the Assumption did not come out of thin air in 1950. Christians taught similar doctrines for centuries—it wasn’t a defined dogma in the Catholic Church, and Pius XII proclaimed it ex cathedra, but it was not by any means a new belief, nor is it unique to Latin Rite Catholics.

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