I would like to note, though, that I will be attempting to keep the tone fairly conversational. I'm not a theologian and this isn't a research paper. While I hope to draw on much better resources than myself, I plan on writing these as if you had just asked me the question while we were at coffee. It's an informal introduction, which means less work for me and hopefully a more accessible form for most. So...let's talk about Mary
The way I think of Mary is as a completely unique figure in the Bible. She stands apart. Growing up evangelical, I used to list her right alongside any other famous biblical figure: Jacob, Samson, Ruth, Noah, etc. She was interesting in her own right but nothing special. Just a woman.
Even when I became Catholic, though I had something of a Marian vision before my conversion, I still was pretty uncomfortable with the emphasis on Mary. I couldn't understand it, let alone relate to it.
But eventually I picked up a book by Scott Hahn called, Hail, Holy Queen. Hahn does a good job of simply explaining a lot of Catholic beliefs even if his conclusions seem to make significant jumps at times.
If you know anything about Christ you probably know that he existed before everything else. And he was part of a plan conceived long before his birth in 1st century Palestine. "Typology" refers to the study of "types", literal people, things, and events in the Bible that foreshadowed and pointed toward an antitype, Christ himself. We see types of Christ in Moses the deliverer, Isaac who was (almost) the spotless sacrifice, the lamb's blood at Passover, etc. Most of us have heard these often enough.
Adam is another one. Christ is even called the "New Adam" because while sin and death entered the world through Adam, salvation and eternal life entered creation through the New Adam - Christ.
Catholics see Mary in a similar light when it comes to types and foreshadowing. We believe she was such a crucial part to God's plan that God chose her specifically, before she was even born, to be the "mother of God." This is the immaculate conception - Mary's conception without sin in her mother's womb and not Christ's conception. A lot of people mix up the meaning of that term. It's for Mary. We'll come back to that.
There are types for Mary too. We see this in figures like Sarah, Hannah, and Esther. Sarah miraculously conceives of a son (who is blamelessly offered as a sacrifice, remember?). Hannah again conceives miraculously and gives her son back to God. And Esther intercedes with the king on behalf of her people just as Catholics believe Mary intercedes for us with Christ the King, on our behalf. That belief didn't come from wishful thinking; it came from exegesis and Scripture.
And like Christ as the New Adam, Mary is considered the "New Eve". Salvation and the gift of eternal life (read "Christ") entered the world, literally, through her, and so it's a much more elevated picture of Mary than merely another woman in the Bible.
The Ark of the Covenant was a symbol of God's presence with his people, Israel. Inside of it was contained the stone tablets of the Ten Commandments, the priestly rod of Aaron, and manna from Heaven. We could describe these contents also as the Word of God, the symbol of the high priest, and life-giving bread. The Word, High Priest, and the Bread of Life. It's easy to see how these are types of Christ.
But wasn't the ark itself holy? And didn't it too have great significance? If it did not derive significance from what it held, it would merely have been 'some box' and there would have been no effort to dress it up or beautify it, let alone describe it for us in the Old Testament. The ark itself is actually a type for the antitype of Mary. Mary herself, therefore is thought to be exceptionally holy and kept without sin (immaculate conception) by God's grace in order that she might carry and bring forth Jesus, just as the ark was holy because of its contents.
Some other quick things on Mary. Catholics call her the Queen of Heaven. This is modeled on the "queen mother" in the Old Testament. Bathsheba and Solomon are the types here for Mary and Christ. She intercedes with the king on behalf of others.
Catholics believe that not only was she conceived without sin but she remained perpetually a virgin. They believe Christ was her only child ever and because she was free from sin, she did not suffer the wages of sin - death. This is the Assumption. We believe Mary was assumed into heaven. Those references to "brothers and sisters" of Christ or to James as "the brother of Christ" are actually mistranslations of, I believe, the Greek adelphos, which does mean sibling but is used elsewhere in Scripture to mean "cousin." And if Christ had siblings, Catholics hold, why did he entrust Mary to John when he was dying and said, "behold your mother"?
Catholics believe Jesus gave us all his mother with these words. We honor her and never worship her. She's the New Eve, foreshadowed in the Old Testament and even mentioned in Revelation. The theotokos, Queen of Heaven, Our Lady, and our supreme intercessor before the throne of God. We are all brothers and sisters of Christ in faith. And so we're all sons and daughters of Mary in the same way.
The most striking evidence for the truly unique position of Mary for me though is her response to God's plan. She simply says, "Let it be done unto me according to your word." Who among us could say this, ever? Who could so humbly and simply accept God's plan to make us a social outcast? To accept something our religious language never even prepared us to understand, let alone handle such as a virgin birth of God himself? Utterly incomprehensible. Her response isn't just amazing, it's unique. And I don't think anyone else could have done it.
You don't have to believe all of this, of course. But Catholics, Orthodox, and some other Christians do, and it's wise to be sensitive to it. All of this is not to say there aren't critiques even from me on the ways in which Mary has been thought of and used. But you've got the basics now, and that's the point.
