I'm having troubles with the Doctrine of the Immaculate Conception. Why does the Church insist on this dogma, and doesn't it contradict the Bible? Also, if Mary is sinless, then how is she not God (or at least a god)?

In talking a number of my friends who have converted from Protestantism—in particular, Baptist, Evangelical, or Fundamentalist forms of Protestantism—to Catholicism, I've found that there are certain doctrines or dogmas which are always last to be accepted. The Marian doctrines are always among these, and I suspect that if they had to name one doctrine which was hardest of those, it would be the dogma of the Immaculate Conception. The objections aren't always the same, but many are similar:

• Only God is sinless. So if Catholics believe that Mary is sinless too, does that not mean that Catholics make Mary into God (or a god)? Jesus was sinless because He Is God.
• Isn't sin a part of human nature? Then how can Catholics believe that Mary was conceived without sin?
• Doesn't the Bible itself tell us that all of us are sinners—and so doesn't this belief necessarily contradict the Bible?

These are the main objections, though there are also a number of questions which get associated with these, and there are a number of "minor" objections held by different individuals which are no less potent (for those individuals) for not being widespread. Actually to deal extensively with these three "major" objections (let alone the "minor" ones) and to explain the meaning the of dogma, etc would be more than could be dealt with by one post or one RCIA session (etc.) [1].

Although I can't in a single post (or session) build an absolutely convincing case for the dogma of the Immaculate Conception, I think I can give a brief reply to these objections—the first two today, and then the last one next time. It may be helpful to briefly review my short discussion of original sin.

With this explanation of original sin in mind, lets turn to the first two of the objections, each in turn. First, the objection that only God is sinless. Alternatively, being sinless means being perfect, and hence being God. This I would like to disprove by demonstration. First, unless I am horribly mistaken concerning Protestant doctrine (and, for that matter, Jewish belief on the matter), there ought to be no objection to the Catholic belief that sin requires an intellect and a will. This means that inanimate objects, not to mention plants, animals (excluding humans, who are endowed with both intellect and will), and "artificial intelligences" are without sin. Whatever may be its value as a bumper-sticker political slogan, "Guns don't kill people; people kill people" is a reasonable description of how sin works. Guns, rocks, dogs, skyscrapers, robots, trees, etc: these are all sinless. Yet, none of them is thought by anyone to be "perfect," let alone to be God.

But that is a trivial explanation, almost a strawman [2]. Man has an intellect and a will, and is therefore a sinner if he is not God. I am not sure that this conclusion follows either. After all, the angels also have both intellect and will--and those in heaven are also without sin, are they not [3]? They are also not perfect in the absolute sense, though perhaps in the lesser sense of being "perfect angels," that is, in the sense pertaining to their own natures, which are certainly not divine. Therefore, sinlessness does not imply being God [4].

There are actually two more counter-examples which come to my mind [5]. However, these are actually better left as responses to the second objection, to which I now turn. Isn't sin a part of human nature? In "We Believe": A Survey of the Catholic Faitheverything he had made, and found it very good" (Genesis 1:31). Sin cannot be an essential part of the nature of something—Man—which is seen by God to be "good." Man himself was capable of sin, but in his preternatural state of grace, he could not be tempted or otherwise caused to sin through, for example, fear of death, or through ignorance of God's will, or through a weak will which often seeks after "illicit" goods, or through the rebellion of his own flesh against hs will; rather, God's grace allowed man to be tempted in only one way, the temptation to disobey him in this way only: "From that tree [of knowledge of good and evil] you shall not eat; the moment you eat from it you are surely doomed to die" (Genesis 3:17). Man's nature made him capable of sinning, perhaps even likely of sinning, without grace—and so God gave him extra graces at his creation so that He would not sin, would not even be tempted to sin, save in this one little matter, though that is the topic for another day.

That this was a supernatural state and not only a natural one into which man was created is worth restating here. Recall the passage from Mr David Currie's Born Fundamentalist, Born Again Catholic concerning the difference between the Catholic and the Evangelical-Protestant understandings of Man's state at his first creation. I will not dwell on this point just now, but only bring it up to note that Sin was not included in Man's essential nature form the beginning, nor is it in our essential nature now, yet neither the first Man nor any of us is God; nor are we "God-like" in contrast to each other, nor was Adam especially "God-like" in contrast to us. All that he had which we do not was that extra grace with which God endowed him.

What about the other example of humans being without sin? I've covered Adam and Eve, Jesus Is given since He is also God, and Mary would be question-begging as an example. What's left? What is left is that "cloud of witnesses" which is collectively the souls of the faithfully departed; and indeed, all people who will live forever with God in the New Heaven or on the New Earth (Revelation 21:1). We will all still be human in our nature—yet we will no longer be sinners. After all, in Heaven "there shall be no more death or mourning, wailing or pain" (Revelation 21:4), and "but nothing unclean will enter it" (Revelation 21:27), that is, there will be no further sinning in Heaven. We will in fact be cleansed of our sins before entering heaven.

If it is really to be us who enter heaven, we as ourselves in our nature as human beings, this means that sin itself cannot be an essential part of our nature. It can only be an accidental part of our nature, a thing which can be removed (as by God's grace) from our nature without our identity as human beings changing. So if there are to be human beings in heaven in the next life, then sin cannot be an essential part of our nature.

Our Lady's Immaculate conception points us to this, by showing that through God's own grace a human being who is not God can be restored to the state in which our species was originally created, by showing us that sin is not to be our destiny. She was preserved from all stain of sin through a singular act of God's grace, it is true: but all who enter into heaven for eternity shall one day experience this grace for ourselves. Indeed, it is a slightly more perfect state of grace than even the one in which Adam and Eve lived, because in their case, God left open the door for a single possible temptation, to which they ultimately succumbed; in the case of the blessed in their supernatural state of grace, even this one temptation will not be so tempting.

----Footnotes----
[1] I would recommend that the interested reader read Dr Scott Hahn's Hail, Holy Queen or Mr Mark Shea's Mary, Mother of the Son trilogy (available here, my reviews of this are found here, here, and here).

[2] Also sinless, I would imagine, unless one means the Strawman from Wizard of Oz, about whom I do not think there is a formal doctrine per se.

[3] The ones who have sinned are Satan and the other "fallen" angels, those who are in Hell. But not all of the angels fell, as we have plenty of Scripture verses to show. There are saints Michael, Raphael, and Gabriel for example, and the Seraphim and Cherubim as entire choirs. I'm not exactly an expert of angelology, but I can think of only one example of a non-fallen angel sinning (after a sort), and that is in J.R.R. Tolkien's The Silmarillion: which is a work of fiction!

[4] That assumption is that God has the attributes of being morally perfect, as well as having knowledge and power which exceed all other knowledge and power. The assumption is sometimes called "theistic personalism," and it makes God into the highest class of being, but ultimately falls short of the Catholic understanding of God. The Catholic understanding is that God is absolutely simple--this is called "divine simplicity." God does not have all of these attributes, e.g. of being powerful or good or wise; rather, He IS His power, which IS His wisdom, which IS His goodness.

[5] Excluding, of course, Saint Mary's own Immaculate Conception. That would just be question-begging and circular arguing, now, wouldn't it?

[6] I hate to throw terms around unnecessarily. However, in this case I think I need to introduce another term: "substance." Philosopher Charles de Konninck, in his essay The Hollow Universe, arrives at the following definition for substance: "that which is in itself and not in another." Another term, essence, is the attributes of a substance which makes it what it fundamentally is. And a final term, "accident," which is any property an object or substance holds contingently; a substance can lose any of its accidental properties without loses its essence, its identity. A philosopher with Aristotelian-Thomistic leanings might explain that sin is an accidental part of our nature, but not an essential part, so that a sinless man (e.g. Christ) still has the fullness of human nature, with all the essential attributes of humanity.