Whether you chose to believe Mary remained a Virgin or not, why is it so significant to Catholics that Mary had remained a Virgin after the birth of Christ? It would not have been sinful for her to have relations with her husband and beget other children.
Salvation is through Chris alone! Mary is not a saviour and she recognized who is the saviour (Luke 1:47 greek - “theO tO sOtEri mou,” “God THE SAViour OF-ME.”
So why is it so significant to Catholics that Mary had remained a Virgin after the birth of Christ? Would it cause the means to salvation to change? No!
Have not absorbed all that was said but a few comments on the OP here.
The question seems awkward to me since it sort of implies that there is a theological motive for Catholics to embrace and defend The PVoM doctrine independent of that God wants and what is an actuality. We embrace and defend for no other reason than because it is a revealed divine truth - there are no external motives other than propegating the faith/truth.
This dogma pulls together and harmonizes a LOT of OT topology with NT fulfillment and fulfills prophecy and just makes perfect sense.
We can speculate about why God wanted a virgin for His Mother from the obvious condition of His Majesty. It would be proper that no other man would be involved in relations for that reason alone. It would also be proper and fitting that there could never be any question about children being of human estate or of human-divine estate or any clouding of the inheritance imagery that is so important to the ancient Jewish traditions. Since Adam’s fall the procreative act is also tainted in that any child born of human intercourse must inherit sin from its parents. I don’t recollect the conventional belief as to which parent was seen in ancient times to be the carrier of the taint of sin or if both were. But by having perpetual virgin bear God’s child he is immediately broadcasting that something quite exceptional going on - no chance for inherited sin since the child was not conceived by human to human intercourse. But further it also ratifies many prophecies that speak of David’s Key and the East Gate that Ezekiel speaks of which no man but the Lord can enter and exit – these call all be seen as topologies of Mary and her Virginity:
*Rev 3:7 He who is holy, who is true, who has (D)the key of David, who opens and no one will shut, and who shuts and no one opens, says this:…
“This gate shall be shut, it shall not be opened, and no man shall
enter by it, because the Lord God of Israel has entered by it; therefore it
shall be shut” (Ez. 44: 1 -2). The prophet saw the glory of the Lord at this
gate which is in the East, and the house was filled with it (Ez. 43: 2,4,5).
From Eastern thought this symbolises the virginity of the Virgin who was from the
countries of the East; and how this virginity remained sealed.
Because she was that gate from the East, she was qualified as:
19. The gate of life, the gate of deliverance:
It was said about our Lady the Virgin in the book of Ezechiel: “As
for the prince, because he is the prince, he may sit in it to eat bread before
the Lord; he shall enter by way of the vestibule of the gateway, and go
out the same way” (Ez. 44:3). Since the Lord is the Life, then she is the gate of the Life. The Lord said: “I am the resurrection and the life” (John 11:25). That is why the Virgin can be said to be the gate of the Life, that gate out of which the Lord came out,
granting life to all those who believe in Him.
It is not astonishing that we surname the Virgin “the gate”, because
the Church also was surnamed “the gate”. Our father Jacob said about
Bethel: “How awsome is this place! This is none other than the house of God, and this is the gate of heaven!” (Gen. 28:17). 20. She was compared to the “Holiest of all”. That in which the chief priest entered once a year, to make atonement for all the people. The Lord of glory came once inside the Virgin Mary for the redemption of all the world.
*
Also from Paul’s NT accounts of Jesus as new Adam it is fairly straightforward to see that God is provisioning new spiritual parents for a new elevated humanity reborn through new divine-human and sinless human estate in a new cooperative between God and man. Mary is clearly the New Eve and for her to be “blessed above all women” she would need to be created sinless and never fall as did Eve. Perpetual Virginity would remove any doubt that Mary was blessed above all women and uniquely special as the Mother of God and also the mother of a new Humanity that was now spiritual in nature. So Jesus as Mary’s savior pre-saved her from ever sinning by shepherding her away from all occasions of sin with a supernatural presence of “voice” where Mary always followed Him the instant of her conception. If God can grant the miracle of the incarnation Jesus it is “child’s play” for God to also preserve Mary from original sin ( a different topic). Mary is the new arc of the new covenant and no man may touch her under penalty of death (ref. 1 Chron 13:10 Uzza touching the arc and instantly dieing)
Just wanted to put a few ideas out there to help prime the pump further.
James