To speak of our Lady is never repetitive. For the human intellect, speculation on her greatness is inexhaustible, because She, though a creature, is a perfect reflection of God’s immense greatness.

The truth of the Immaculate Conception was proclaimed as an infallible dogma of the Church by Blessed Pius IX on 8 December 1854, with the bull Ineffabilis Deus, with which the pope defined that the Virgin Mary was preserved from original sin from the first instant of her conception.

The foundation of this Marian privilege lies in the absolute opposition, the infinite irreconcilability, between God and sin. In contrast with man, conceived in sin, is Mary, conceived without shadow of sin, most pure and spotless. And since sin is a disorder of the intellect and will, to Mary, as the Immaculate, it is reserved to conquer every evil, error and heresy that arises and develops in the world as a consequence of sin.
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When Pius IX ascended the papal throne in 1846, a centuries-old Revolution aimed at destroying the Christian social order was coming to a head. One of its ideological foundations was the denial of original sin. The naturalistic and rationalistic liberal and socialist system held, in fact, that the greatness and progress of man were the supreme goal of history and that modern man had to become self-sufficient and “come of age”, freeing himself from the tutelage he had until then received from the Church.
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Our Lady, therefore, as she stands out against the grandiose backdrop of Ineffabilis Deus, is the “glorious vanquisher of heresies” of which all the pontiffs speak, and the contrast between the “all beautiful and Immaculate” Virgin and the “most cruel serpent” makes manifest the first and fundamental agents of the radical antagonism between the Church and that Revolution of modern times that has its most active and deeply rooted seeds precisely in the disorder of the passions and the intellect, father of every error and heresy and fruit of the sin of fallen man.