. . . the basic principle upon which Mary’s royal dignity rests, a principle already evident in the documents handed down by the ancients long ago and in the sacred liturgy, is without doubt her Divine Maternity. In the Sacred Scriptures we read this statement about the Son Whom the Virgin will conceive: “He shall be called great, and shall be called the Son of the Most High; and the Lord God will give Him the throne of David His father, and He shall be King over the house of David forever; and of His Kingdom there shall be no end.”40 And furthermore, Mary is called the “Mother of the Lord.”41 From this it is easily deduced that she too is Queen, since she brought forth a Son Who, at the very moment that He was conceived, was, by reason of the hypostatic union of the human nature with the Word, even as man, King and Lord of all things. As a result, St. John Damascene could rightly and deservedly write these words: “Truly she has become the Lady Ruler of every creature, since she is the Mother of the Creator.”42And it can likewise be said that the first one, who with heavenly voice announced Mary’s royal office, was Gabriel the Archangel himself.
35. Now, the most Blessed Virgin Mary is to be called Queen, not only by reason of her Divine Maternity, but also because by the will of God she has had an outstanding part in the work of our eternal salvation. “What more pleasant or sweeter thought could we have,” wrote our Predecessor of happy memory, Pius XI, “than that Christ rules over us, not only by native right, but also by an acquired right, namely that of the Redemption? Would that all men who have forgotten how much we have cost our Savior might remember: ‘You were redeemed… not with perishable things, with silver or gold, but with the Precious Blood of Christ, as of a lamb without blemish and without spot.’43 We are no longer our own for ‘at a great price’44 Christ has purchased us.”45
36. Now, in accomplishing this work of the Redemption, the Most Blessed Virgin Mary was certainly intimately associated with Christ. Appropriately, therefore, we sing in the sacred liturgy: “Holy Mary, the Queen of Heaven and the Lady Ruler of the world was standing, sorrowful, by the Cross of Our Lord Jesus Christ.”46 Wherefore, as even in the Middle Ages, a very pious student of St. Anselm wrote, “As… God is the Father and Lord of all things, preparing all by His power, so the Blessed Mary, repairing all things by her merits, is the Mother and Ruler of all. For God is the Lord of all things, in each constituting by His Command in its own nature, and Mary is the Lady Ruler of all in restoring each to its original dignity through that grace which she has merited.”47
37. As Christ is our Lord and King by a special title because He redeemed us, so the Blessed Virgin [is our Lady and Queen] because of the unique way in which she has cooperated toward our Redemption by giving of her own substance, by offering Him willingly for us, and by desiring, praying for, and bringing about our salvation in a singular manner.48
38. From these premises the following argument is drawn. Mary was, by the will of God, associated with Jesus Christ, the Principle of salvation itself, in bringing about spiritual salvation in a way that was quite similar to the way in which Eve was associated with Adam, the principle of death, so that it may be said that the work of our salvation was accomplished through a certain “recapitulation,” in which a virgin is instrumental in saving the human race, just as a virgin was instrumental in making it subject to death.49 Moreover, it can also be said that this most glorious Lady was the beloved Mother of Christ precisely “so that she might be made His associate in the Redemption of the human race.”50 Actually, “It was she, the second Eve who, free from all sin, original or personal, and always most intimately united with her Son, offered Him on Golgotha to the Eternal Father for all the children of Adam, sin-stained by this unhappy fall, and her mother’s rights and mother’s love were included in the holocaust.”51 Hence we may certainly conclude that just as Christ, the new Adam, must be called King, not only because He is the Son of God, but also because He is our Redeemer; so, by a certain kind of analogy, the most Blessed Virgin is Queen, not only because she is the Mother of God, but also because, as the new Eve, she was associated with the new Adam.
39. And so it is that Jesus Christ alone, God and man, is King, in the full, proper, and absolute sense of the term. Yet Mary also, although in a restricted way and only by analogy, shares in the royal dignity as the Mother of Christ Who is God, as His Associate in the labors of the Divine Redemption, and in His struggle against His enemies and in the victory He won over them all. From this association with Christ the King, she obtains a splendor and eminence surpassing the excellence of all created things. From this association with Christ comes the royal function by which she can dispense the treasures of the Divine Redeemer’s Kingdom. Finally, from this association with Christ comes the unfailing efficacy of her maternal intercession with the Son and with the Father.
Venerable Pope Pius XII
Ad Caeli Reginam