The Dormition is the central focus of the disagreement between Eastern and Western Christianity over original sin and the Immaculate Conception. The Western view of the Immaculate Conception is described most succinctly and precisely in the bull defining the Immaculate Conception, Ineffabilis Deus of Pope Pius IX:
The East, by contrast, has often been said to reject this dogma. I use the phrase "often been said" because ample documentary evidence can be touted to the contrary, including many prayers said on a daily basis in the Orthodox Church which seem to teach the Western dogma of the immaculate conception (like the prayer "More honorable than the cherubim and beyond compare more glorious than the seraphim..."), the use of the phrase by Ukrainian Orthodox luminaries like St. Peter Mohila in the 17th century, the Mariology of St. Gregory Palamas, etc. etc., which are worthy of consideration in a post in their own right. The actual disagreement over the Immaculate Conception boils down to a difference in the notion of original sin considered in its application in different interpretations as to what happened at the Dormition. The East uses the phrase "original sin" (or the more common phrase "ancestral sin") to mean death; the West uses it to mean the reatus inherited from Adam's sin (a Latin word often mistranslated as "guilt", though it is not synonymous with "culpa"). The difference on original sin will be explored in more depth in a subsequent post; for now, it suffices to say that from the viewpoint of the East whether the Theotokos was immaculately conceived depends entirely on whether she died or not.We declare, pronounce and define that the doctrine which holds that the Blessed Virgin Mary, at the first instant of her conception, by a singular privilege and grace of the Omnipotent God, in virtue of the merits of Jesus Christ, the Saviour of mankind, was preserved immaculate from all stain of original sin, has been revealed by God, and therefore should firmly and constantly be believed by all the faithful.
A venerable Dominican theologian, Fr. Ryan Erlenbush of the New Theological Movement (http://newtheologicalmovement.blogspot.com/2011/08/death-of-blessed-virgin-mary-latin.html), has argued that the Dormition (passing) of the Theotokos is just as strong a tradition in the West as in the East. If so, one must still ask the question why the Theotokos died. Did she have to die, or was her death a free choice like that of Christ's? In the East, it is considered dogmatic that the Theotokos had to die - it is in this sense, and this sense alone, that the Theotokos was subject to any taint of Adam's fall. In the West, it is taught that she did not have to die, but willingly chose death in order to unite herself to the death of her Son (as I was taught when being instructed in the Faith by a Roman Catholic priest before being received into full communion with Rome). As a Greek Catholic seeking to show the perfect harmony between both lungs of the Church, I would like to argue that these two views are in fact compatible with each other. I will take my cue from St. Dimitri Tuptalo, the Latinophile Orthodox archbishop of Rostov who received his seminary training in Rome (while remaining Orthodox) and was known to pray the Angelus on a daily basis and go on pilgrimages to Greek Catholic shrines in Belarus.
St. Dimitri, an Orthodox theologian and saint, also argued that the Theotokos chose to die in order to unite herself to the sufferings of her Son. How then do we reconcile this with the East's insistence on the necessity of her death? One must consider that as the all-pure Mother of God, she lived in the deepest expression of the truth, in the fullest grounding in reality. It is impossible that one as holy as the Mother of God should be bound and enslaved to matter, something less than her; as the New Eve, she lived the fullness of the freedom given by the Holy Spirit, and could not have been carnal in the Pauline sense (in the sense of being enslaved to and unable to transcend matter, rather than matter serving your good). She chose to die because she willed reality into being, co-operating with God in willing the creation of the world and the nature of its denizens (including the consequences they received from original sin), and therefore willed her own death as part of the way things are supposed to have worked. Christ told some saint that He does nothing without asking His mother, and this includes her death, the necessary consequence of the ancestral sin.
It is truly a wonderful thing to will one's own reality. Sartre said that "man makes himself", and Kierkegaard often spoke of man's authenticity, and in the Theotokos we saw the perfect example of this, where will and truth are perfectly united. Sartre never understood any of his words anywhere close to the full depth of their meaning.
The Theotokos could not lay down her own life as her Son could. But she abided in prayer, and as the only human being "full of grace", perfectly divinized, she was omnipotent through her prayer, for God never refuses His Mother. It was through the prayer of the Mother of God that her Dormition was both a necessity of the ancestral sin and her own free choice.