The Mother of the Redeemer
and of All Men
These two titles are evidently connected. We shall consider them in the order indicated.
The Church calls Mary Mother of the Savior as well as Mother of God. In the Litany of Loreto, for example, after the invocations, 'Holy Mother of God,' and 'Mother of the Creator,' we find the other, 'Mother of the Savior, pray for us.' Though some have thought the contrary,  the fact of these two titles is no reason for believing that Mariology labors under the defect of a duality of distinct principles: 'Mother of God' and 'Mother of the Savior, who is associated with His redemptive work.' Mariology is a unity, for Mary is 'Mother of God the Redeemer or the Savior.' In much the same way the two mysteries of the Incarnation and the Redemption do not take away from the unity of Christology, for its central point is the redemptive Incarnation. The motive of the Incarnation is sufficiently indicated in the Creed which says that the Son of God came down from Heaven for our salvation.
Let us now see how Mary became Mother of the Savior by her consent, and how, as Mother of the Savior, she was to be associated with His redemptive work.
Mary Became Mother of the Savior by Her Consent
Mary gave her consent to the redemptive Incarnation when, on the day of the Annunciation, the angel said to her: 'Thou shalt conceive in thy womb, and shalt bring forth a son; and thou shalt call his name Jesus' --- the name to be given to her Son meaning' Savior.' Mary was not ignorant of the Messianic prophecies --- most particularly those of Isaias --- which foretold the redemptive sufferings of the promised Savior. Thus, when she uttered her fiat she accepted in advance for herself and for her Son all the sufferings which the redemption would involve.
She learned something still more explicit about them a few days later when Simeon spoke to her: 'Behold this child is set for the fall, and for the resurrection of many in Israel, and for a sign which shall be contradicted; And thy own soul a sword shall pierce.' A little earlier he had spoken of Jesus as '. . . thy salvation, which thou hast prepared before the face of all peoples.' Mary, we are told, kept all these words in her heart. The Divine plan became gradually clearer to her contemplative faith, lit up as it was by the illumination of the gift of --- Mother of the Redeemer in His of Redeemer; she grew in her appreciation of the fact that the Son of God became Man for our salvation. She united herself to Jesus as only a mother, and a very holy mother, could in perfect oneness of love for God and souls. That was her way of fulfilling the great precept of the law --- and what more perfect way could there be? Tradition is clear on Mary's union with the Redeemer; it never tires of that as Eve was united to the first man in the work of perdition Mary was united to the Redeemer in the of redemption.
Mother of the Redeemer, she grew too in her appreciation of the manner of our redemption. It was sufficient for her to call to mind and meditate on the prophecies which all knew so well. Isaias (liii, 1-12) announced the sufferings and humiliations of the Messiah, saying that they would be borne to expiate our sins by Him Who is innocence itself, and that by His Death He would justify many. She knew too David's psalm (Ps. xxi) 'O God, My "God, why has thou forsaken me?' describing the prayer of the Just One, His cry of anguish in His abandonment, and His confidence in Jahve, His apostolate and its effects in Israel and among the gentiles. There was finally Daniel's prophecy of the Son of Man (Dan. vii, 13-14) and of the power that would be given Him: 'And he gave him power, and glory, and a kingdom: and all peoples, tribes, and tongues shall serve him: his power is an everlasting power that shall not be taken away: and his kingdom, that shall not be destroyed.' All Tradition has seen the Messiah promised as Redeemer in the Man of Sorrows of Isaias and the Son of Man of Daniel.
Mary, who was not ignorant of these prophecies, became therefore Mother of the Redeemer in His role of Redeemer at the Annunciation. From her consent 'Be it done to me according to thy word' follows all the rest of her life, just as all Jesus' life followed from the consent He gave to His Father's will on entering the world: 'Holocausts for sin did not please thee. Then said I: Behold I come to do thy will, O God' (Hebr. x, 6, 9). The Fathers could say that our salvation depended on Mary's consent, and that she conceived her Son spiritually before she conceived Him corporeally. 
It may be objected that a Divine decree such as that of the Incarnation could not depend on the consent of a creature who was free not to give it. To this theology answers that God has efficaciously willed and infallibly foreseen everything that will happen in the course of time. Therefore, He willed efficaciously and foresaw infallibly Mary's consent to the realization of the mystery of the Incarnation. From all eternity God, Who works with strength and gentleness, decided to give Mary the efficacious grace which would move her to consent freely and meritoriously. Just as He makes the trees to bear their blossoms, so He makes our wills to produce their free acts; and far from doing them any violence He is the author of their freedom, for that too is a reality, a form of being. The 'how' of all this is the secret of God Omnipotent. Just as Mary conceived the Savior by the operation of the Holy Ghost without losing her virginity, so she uttered her fiat infallibly under the motion of efficacious grace without prejudice to her complete liberty --- rather did her will, under the Divine motion, flower spontaneously into the free consent she gave in the name of all mankind.
Mary's fiat belonged entirely to God as First Cause and entirely to Mary as secondary cause. In it we find a perfect example of what St. Thomas speaks of (Ia, q. 19, a. 8): 'Since the will of God is supremely efficacious it follows that not only do the things that God wills (efficaciously) happen, but that they happen in the way in which He wills. But it is His will that some things should happen of necessity and others freely.' By her fiat, then, Mary became voluntarily the Mother of the Redeemer.
Tradition recognizes that Mary consented to be Mother of the Redeemer in His redemptive role by calling her the New Eve. The first Eve, by consenting to temptation, led the first man to commit the sin which lost original justice for mankind. Mary is the New Eve by her consent to be the Mother of the Redeemer for the sake of the work of redemption.
Some non-Catholics have objected that Mary's parents could equally well have been entitled father or mother of the Redeemer and regarded as associated with Him in the work of redemption. It is not hard to find an answer to this objection. Mary alone received the light required for the consent of which we speak. Her parents did not know that the Messiah would be born of their family. St. Anne could not foresee that her child would be the mother of the Messiah.
How Was the Mother of the Redeemer to be Associated with His Work?
According to what the Fathers of the Church tell us about Mary as the New Eve whom many saw foretold in the words of Genesis, it is common and certain doctrine, and even fidei proxima, that the Blessed Virgin, Mother of the Redeemer, is associated with Him in the work of redemption as secondary and subordinate cause, just as Eve was associated with Adam in the work of man's ruin. 
The doctrine of Mary as the second Eve was universally accepted in the 2nd century. The Fathers who taught it then did not regard it as the fruit of personal speculation but as the traditional doctrine of the Church supported by the words of St. Paul which describe Jesus as the second Adam and oppose Him to the first as the Author of salvation to the author of the fall (I Cor. xv, 45 sqq.; Rom. v, 12 sqq.; I Cor. xv, 20-23). They fitted St. Paul's words into the context of Genesis' account of the fall, the promise of the redemption, and the victory over the demon, as well as St. Luke's account of Mary's consent at the Annunciation. It is necessary therefore to regard the doctrine of Mary as the second Eve, associated with the redemptive work of her Son, as a divino-apostolic tradition. 
The Fathers who speak most explictly of this matter are St. Justin,  St. Irenaeus,  Tertullian,  St. Cyprian,  Origen,  St. Cyril ofJerusalem,  St. Ephrem,  St. Epiphanius,  St. John Chrysostom,  St. Proclus,  St. Jerome,  St. Ambrose,  St. Augustine,  St. Basil,  St. Germanus of Constantinople,  St. John Damascene,  St. Anselm,  St. Bernard.  In later times the theologians of the middle ages and of our own day have maintained the same doctrine. 
What, according to Tradition, is the sense in which Mary, the New Eve, was associated with the work of redemption?
It was not merely by having conceived the Redeemer physically, by having given Him birth and nourished Him, but rather was her association moral, through her free, salutary, and meritorious acts. Eve contributed morally to the fall by yielding to the temptation of the devil, by disobedience, and by leading up to Adam's sin; Mary, on the contrary, co-operated morally in our redemption by her faith in Gabriel's words, and by her free consent to the mystery of the redemptive Incarnation and to all the sufferings it entailed for her Son and for herself.
Clearly, Mary is not the principal and perfective cause of the Redemption: she could not redeem us in justice, de condigno, since for that a theandric act ofinfmite value which could belong only to an incarnate Divine Person was required. But she is really a secondary cause of salvation, dispositive, and subordinate to Jesus. She is said to be subordinated to Jesus not merely in the sense that she is inferior to Him, but also in the sense that she concurred in saving us by a grace which proceeded from His merits, and therefore acted in Him, with Him, and by Him. We must never forget that Jesus is the Universal Mediator. He redeemed Mary by preserving her from Original Sin. Similarly, it is through Him that she contributed to saving us. She is not the perfective cause of salvation, but a dispositive one, disposing us to undergo the action ofher Son, Who it is achieves our salvation and is our Redeemer.
Mary's association with Jesus in the redemption is therefore not like that of the Apostles, but is something still more intimate. That is what St. Albert the Great formulated so happily when he said: 'The Blessed Virgin Mary was chosen by God not to be His minister but to be His consort and His helper-in consortium et adjutorium ---- according to the words of Genesis: Let us make him a help like to himself' (Mariale, q. 42).
We can now see that the unity of Mariology does not suffer from the defect of having two distinct principles. There is one principle which dominates it: Mary is Mother of God the Redeemer and is by that fact associated to His work. In the same way, the two mysteries of the Incarnation and the Redemption do not constitute a duality so as to take from the unity of Christology, for they fmd themselves united in the idea of the redemptive Incarnation; and their union in it is expressed in the Creed in the words' . . . qui propter nos homines et propter nostram salutem descendit de caelis, et incarnatus est'.
Sonship of God or His grace of hypostatic union is greater than His
of created grace and our redemption. In the same way Mary's motherhood
of God is greater than her fulness of grace which overflows on us, as
been shown in the first chapter of this book. The unity of theological
knowledge contributes to its certainty, since, because of its unity, it
uses subordinated and not co-ordinated principles. All the different
too, which go to make it up are subordinated in their totality to some
Rev. Professor Bittremieux in De supremo principio Mariologiae,
theol. Lovan.,I93I, though he does not deny that in a sense
can be reduced to one principle, insists rather on duality. As against
this cf. Merkelbach, Mariologia, pp. 91 sqq.