Today, December 8th, is celebrated one of the most heartfelt and popular feasts dedicated by the Catholic Church to the Virgin Mary: the Feast of the Immaculate Conception. It falls on the the day when, in 1854, Pope Pius IX, through the papal bull entitled “Ineffabilis Deus” (Ineffable God), sanctioned that the Virgin Mary, by means of “a singular grace and privilege”, had been preserved from that common heritage of the human race, which is original sin, from the first moment of her conception. This formulation follows a long series of theological disputes about the birth of the mother of Jesus. In the East, from as far back as the sixth century AD, there was a celebration of the conception of Mary, which was widespread in the West from the 10th century onwards. The solemnity of the Immaculate Conception of the Virgin Mary is inserted within the context of Advent and Christmas, thus the expectation of the birth of Christ is awaited through the remembrance of the Mother.