Dear Af,
The doctrine of the immaculate conception of Mary is important to the Catholic Church’s understanding of redemption because it speaks of who God is. It is a fact of Scripture that Mary was His choice as the channel through which Jesus became incarnate. He singled her our for this truly sublime mission.
When Catholics make great show of their appreciation of Mary, this is not to take away from Her son. It’s just the opposite. If Mary is so special, how much MORE so is her son!
It is only because of who He is that Mary is so significant. Certainly, we would not want a mother for Him to be any less than what we Catholic believe Mary is!
Fr. Vincent Serpa, O.P.