Why was Mary assumed into Heaven? Why did her soul not leave her body to decay in the earth, like ours will until the end of time?
The Catholic Church believes that Mary was conceived without sin. By the grace of God, she was preserved from the stain of original sin. This is fitting for the woman who would become the Mother of God and the Queen of Heaven. Her womb would bear Christ.
Because she did not have original sin, she did not have to bear the consequence of the fracture that occurred when Adam and Eve sinned. When God created Adam and Eve, He created them as perfect human beings—the body and soul were one, united. When they sinned, there was a fracture between our spiritual nature (our soul) and our bodily nature (we humans are both spirit and body; angels, on the contrary, are only spirit). This fracture is part of our fallen nature, what causes us to sin. It is not a total and complete fracture—it can be repaird through Christ, but because of this fracture, our flesh becomes opposed to our spiritual nature. Our fleshly desires are sinful, and go against what our soul desires in God.
This fracture is evident when we die: our soul leaves the body to go on to Heaven, and our bodies stay behind to decay. Death is a consequence of Original Sin.
But Mary did not have Original Sin. So, when her earthly life ended, God was able to assume her up into Heaven body and soul. Her body did not have the consequence of decaying here on earth.
One day, at the end of time, at the Final Judgment, God will raise our bodies as well, and the fracture between the flesh and spirit will be completely healed. We will be perfect again.
So how do we know that Mary was preserved from sin. Well, the first reading today speaks of “the ark of the covenant”, alluding that “the woman” was the ark. And in this reading, the woman bore a child, and the red dragon wished to devour it, but God catches the child, the ruler of nations, up to his throne. This has been interpreted to mean that Mary is the woman, the child is Christ, and the dragon is the devil.
So why is it important that Mary is the “ark of the covenant”? Really, she is the Ark of the New Covenant, prefigured in the Old Testament with the Ark of the Old Covenant. We can see her prefigurement in what the Ark of the Old Covenant contained. As Catholic.com says:
“The Old Testament tells us that one item was placed inside the Ark of the Old Covenant while in the Sinai wilderness: God told Moses to put the stone tablets with the Ten Commandments inside the ark (Deut. 10:3–5). Hebrews 9:4 informs us that two additional items were placed in the Ark: ‘a golden urn holding the manna, and Aaron’s rod that budded.’ Notice the amazing parallels: In the ark was the law of God inscribed in stone; in Mary’s womb was the Word of God in flesh. In the ark was the urn of manna, the bread from heaven that kept God’s people alive in the wilderness; in Mary’s womb is the Bread of Life come down from heaven that brings eternal life. In the ark was the rod of Aaron, the proof of true priesthood; in Mary’s womb is the true priest. In the third century, St. Gregory the Wonder Worker said that Mary is truly an ark—‘gold within and gold without, and she has received in her womb all the treasures of the sanctuary.’”
In the Old Testament, the ark was required by God to be perfect, and he plans a very details account of how it is to be constructed. To quote from Catholic.com
“The third and most compelling type of Mary’s Immaculate Conception is the ark of the covenant. In Exodus 20 Moses is given the Ten Commandments. In chapters 25 through 30 the Lord gives Moses a detailed plan for the construction of the ark, the special container which would carry the Commandments. The surprising thing is that five chapters later, staring in chapter 35 and continuing to chapter 40, Moses repeats word for word each of the details of the ark’s construction.
Why? It was a way of emphasizing how crucial it was for the Lord’s exact specifications to be met (Ex. 25:9, 39:42-43). God wanted the ark to be as perfect and unblemished as humanly possible so it would be worthy of the honor of bearing the written Word of God. How much more so would God want Mary, the ark of the new covenant, to be perfect and unblemished since she would carry within her womb the Word of God in flesh.
When the ark was completed, "the cloud covered the meeting tent and the glory of the Lord filled the dwelling. Moses could not enter the meeting tent, because the cloud settled down upon it and the glory of the Lord filled the dwelling" (Ex. 40:34-38). Compare this with the words of Gabriel to Mary in Luke 1:35.”
So, you see, Mary, as the Ark of the New Covenant was perfect, created by God to be the perfect temple for His Son.
That is why she was assumed into Heaven.
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