The Solemnity of the Immaculate Conception - Usus Antiquior Mass - Holy Family

Holy Day of Obligation. On December 8, we honor Mary, our Mother. The Solemnity of the Immaculate Conception is a Catholic feast celebrating Mary's conception without sin. Even though this feast day occurs in the liturgical season of Advent, which prepares for the birth of Our Lord Jesus Christ, the Immaculate Conception refers to the conception of Mary in the womb of her mother, St. Anne. The dogma of the Immaculate Conception asserts that, "from the first moment of her conception, the Blessed Virgin Mary was, by the singular grace and privilege of Almighty God, and in view of the merits of Jesus Christ, Savior of Mankind, kept free from all stain of original sin."