“A great sign appeared in heaven: a Woman clothed with the sun, and the moon under her feet, and on her head a crown of twelve stars. Sing ye to the Lord a new canticle: because He has done wonderful things…” (from the introit for today’s Mass.)
“Through thee redeemed to endless life, thy praise let all the nations sing.”
On this her feast day, we celebrate “that which has been realized in her, the total glorification of our humanity, will be realized for us at the end of time. This privilege is very fitting for her; for she is all-pure, all-holy, whose body was never touched by any slightest shadow of sin, but was always the temple of the Holy Spirit, the Ark of the Covenant, the very Tabernacle of the Son of God. … Mary has been taken up into Heaven because she is the Mother of God. This is the greatest of her privileges., the root of all others and the reason for them…Mary’s Assumption thus confirms us in this great and beautiful truth: we are created and called to union with God. (Father Gabriel of St. Mary Magdalen, Divine Intimacy,).
Another reason exists for the Assumption of Mary; it is a quite practical one and can be proved scientifically. There are some truths that simply cannot, indeed, will not be denied. As such, the beautiful Eucharistic miracles which prove that the Consecrated Host is truly the body and blood (Type AB no less!) of Our Lord Jesus Christ.
And we now have scientific documentation of a process called microchimerism, which refers to the process of transfer of the maternal and infant cells during pregnancy. In other words, scientists now know that it is likely that the Blessed Virgin Mary and Our Lord Jesus Christ each harbor each other’s cells in their bodies. Therefore it is even more credible that Christ Our Lord brought His Mother, body and soul to be with Him in Heaven. (For more on microchimerism, see here, here, and here.)
The presence of her Divine Son’s cells in her body is ample reason for her body not being confined to the grave. And think, her own cells are present in His Sacred Body for all time. Truly, Heart of His Sacred Heart, eternally.
Since Mary was perfectly preserved from original sin, there was never a need for her to die. Yet she did agree to die in justice since her Divine Son and Savior chose to die, she could do no less. Our Most Blessed Mother did die for love of Him, Who was her All. And tenderly, with infinite love, He came to her and with His Angels, brought her up into eternal glory with Him.
“Hence, Mary’s death appears as a holocaust of love. The sacrifice, made under the cross in the greatest spiritual sorrow, was thereby outwardly completed in a sweet and loving manner as in a slumber of love.” (Rev. M. J. Scheeben, Mariology, Vol. II.)
“A slumber of love.” The ancient Church knew well that the death of the Mother of God was a singular event, and they referred to this “slumber of love” as her Dormition, her “falling asleep,” a clear indication that the close of the Virgin’s earthly life was peaceful, unaccompanied by any anxiety or pain. On earth, Mary lived for Jesus and for Him only. When her earthly race was run, Mary’s burning desire to be reunited forever with her Son found its fulfillment. “Now, since it is certain that the Son died of love and that the Mother died of the death of the Son,” wrote St. Francis de Sales (+1622), “we must not doubt that the Mother died of love.” (Source)