Immaculate Conception of Mary. The Roman Catholic Church teaches that Mary herself was immaculately conceived. ~ Mary was filled with divine grace from the time of her conception. ... ~ Mary's immaculate conception was necessary in order for her to give birth later to Jesus without infecting him with original sin.

Why is Mary called the Immaculate Conception?

The doctrine of the Immaculate Conception teaches that Mary, the mother of Christ, was conceived without sin and her conception was thus immaculate. Mary's sinless conception is the reason why Catholics refer to Mary as "full of grace".

Why do we celebrate the Immaculate Conception of the Blessed Virgin Mary?

The feast of Mary's Immaculate Conception is celebrated on December 8, and honors the conception of Mary in her mother's womb without original sin. ... By her Immaculate Conception she was conceived in the fullness of grace, in the state of closest possible union with God in view of her future role as the Mother of God.