[metmom]

Mary’s parents did not have a “magical” union. They had a normal marital union, and their little girl was preserved by a singular grace of Almighty God from all stain of original sin, in view of, and in anticipation of, her Son’s merits on the Cross at Calvary.

Why? Why did Mary need to be immaculately conceived?

Where's the Scripture to support that concept?

[narses]

“Where’s the Scripture to support that concept? “

Pray about it. Do your own research.

[Deo volente]

Mary did not need to be immaculately conceived (free from original sin) in the strict sense of the word “need”. Actually, a better way to put it would be to say that God did not “need” to give her this privilege. For that matter, Christ did not need to suffer such a painful death on the Cross. He could have shed one drop of blood at His circumcision and that would have sufficed to redeem the entire human race. While we're at it, God could have simply forgiven Adam and Eve and set things right in the Garden without the Incarnation altogether.

God is ALL-POWERFUL. He can do whatever He wants. He CHOSE to do things as He did, and that included His plan for Mary. She did not “need” to be preserved from original sin, but it was supremely fitting that She was.