Leo XIII (+1903) writes that “with equal truth may it be also affirmed that, by the will of God, Mary is the intermediary through whom is distributed unto us this immense treasure of mercies gathered by God, for mercy and truth were created by Jesus Christ. Thus as no man goes to the Father but by the Son, so no man goes to Christ but by his Mother” (62).
In another encyclical, Leo XIII explains that in the vocal recitation of the Rosary we address first the Father who is in heaven and then the Virgin Mary. “Thus is confirmed that law of merciful meditation of which we have spoken, and which St. Bernardine of Siena thus expresses: ‘Every grace granted to man has three degrees in order; for by God it is communicated to Christ, from Christ it passes to the Virgin, and from the Virgin it descends to us’” (63). At the end of the encyclical the Holy Father, citing the authority of St. Bernard of Clairvaux, reaffirms that God has given us a “Mediatrix” in Mary, willing “that all good should come to us by the hands of Mary” (64).
In Leo’s Encyclical Adiutricem populi, we read that the Blessed Virgin Mary, “who was so intimately associated with the mystery of human salvation is just as closely associated with the distribution of the graces which for all time will flow from the redemption. … Among her many other titles we find her hailed as ‘Our Lady, our Mediatrix,’ ‘the Reparatrix of the whole world,’ ‘the Dispenser of all heavenly gifts’” (65).
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examining the conciliar text of No. 62 of Lumen Gentium, we read the following:
Taken up to heaven she did not lay aside this salvific duty, but by her constant intercession continued to bring us the gifts of eternal salvation. By her maternal charity, she cares for the brethren of her Son, who still journey on earth surrounded by dangers and difficulties, until they are led into the happiness of their true home. Therefore the Blessed Virgin is invoked by the Church under the titles of Advocate, Auxiliatrix, Adjutrix, and Mediatrix. This, however, is to be so understood that it neither takes away from nor adds anything to the dignity and efficaciousness of Christ the one Mediator (92).