Of course the Blessed Virgin is not a savior and herself needed the Savior; thus she rightly proclaims in her Magnificat that God is indeed her Savior. Her salvation, though, was given at the moment of her conception when the foreseen merits of her Divine Son’s Sacrifice and Resurrection were bestowed on her to prepare her to become the Mother of her Savior. Thus she is the Immaculate Conception.
The significance of her Perpetual Virginity is because each doctrine of the Church is connected to the others. Thus contemplating the mystery of the Perpetual Virginity of Mary reveals not so much her prerogatives and her glorious role in Salvation History, but more reveals Who it is Who was born to such a mother. God does nothing for no reason, thus the Perpetual Virginity of Mary has a great significance, pointing to the unique identity of her Son.
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Consider how would you would react if someone made unfounded claims about your mother? THAT’S how Catholics respond when the graces and prerogatives that God has bestowed on her because of her unique relationship with the Three Persons of the Most Holy Trinity, and as Mother of God Incarnate come under attack.
(From a catechesis of Pope John Paul II on the Blessed Virgin Mary given August 28, 1996.)
The import of the Incarnation is often reduced to a “Jesus and me” salvation that leaves no room for all that He does for us through His Church (Baptism, Eucharist, preservation of authentic apostolic teaching authority, e.g.) that joins us not just to Him but through Him to all Who are in Him (the Communion of Saints) - including His Mother who, because she is His, is also ours. The lack of understanding of Mary’s role in salvation history and her prerogatives as Mother of God is an implicit diminution of the reality of Who Jesus is and what His Church is. This article further explains my point:
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