A reader has asked where support for the Catholic Marian doctrines of Our Lady’s perpetual virginity, the Immaculate Conception and the Assumption of the Blessed Virgin Mary into heaven comes from. He doesn’t say, but I suspect he is a Protestant who is considering the Catholic faith.
I think he needs to read Mary-A Catholic Evangelical Debate by my friend David Gustafson and Mrs Longenecker’s favorite author. It is a complicated matter because it touches on the core and the whole of the Christian faith.
However, the short answer is this: The Marian dogmas come from our reflection on the mystery of the incarnation. Jesus Christ is God made man. In the fullness of time God sent forth his Son born of a woman. (Gal.4.4). The Son of God took his human flesh from his mother. Therefore that humanity had to be sinless. Mary is called ‘full of grace’ (Luke 1.28) If sin is the absence or lack of God’s glory and grace (all have sinned and fallen short of the glory of God) then if Mary was ‘full of grace’ she was not lacking in God’s grace and was therefore sinless. When did that sinlessness begin? It must have begun when her life began. Thus we believe that by a special act of grace (empowered by Christ’s sacrifice on the cross) Mary was preserved from original sin from the first moment of her life. This is what we call the Immaculate Conception.
Mary continued in this Christ-won perfection throughout her life, and part of this perpetual purity is the fact that she remained a virgin her whole life. This we call the perpetual virginity of the Blessed Virgin. One of the results of original sin is death and bodily corruption. As she was preserved from original sin she was therefore delivered from the death and bodily corruption which is the result of this sin. Therefore she was taken up into heaven at the end of her earthly life and this we call the Glorious Assumption of the Blessed Virgin Mary into Heaven.
Anyway, that’s the short version. Read the book for a more detailed debate.