Is Mary Co-redeemer? We begin with two fundamental ideas. The first is that only God can redeem and save us. Redemption involves the forgiveness of sins and also a relationship with the Blessed Trinity - a grace through which God gives himself to humanity.
The second idea is that God accomplishes our redemption through the Incarnation, specifically through the life of Christ (his passion, death, and resurrection). However, there is room for human cooperation, as Mary demonstrated. "Thus, Mary, the daughter of Adam, Mary, consenting to the word of God, became the Mother of Jesus. Committing herself wholeheartedly and impeded by no sin to God's saving will, she devoted herself totally, as a handmaid of the Lord, to the person and work of her Son" (LG 56).
Mary accompanied her Son at the foot of the cross: "the Blessed Virgin advanced in her journey of faith and faithfully remained united with her Son until the cross, following “the Blessed Virgin advanced in her pilgrimage of faith, and faithfully persevered in her union with her Son unto the cross, where she stood (cf. Lk. 2:19; 51), in keeping with the divine plan, enduring with her only begotten Son the intensity of his suffering, associated herself with his sacrifice in her mother’s heart, and lovingly consenting to the immolation of this victim which was born of her” (LG 58).
Furthermore, "in a completely unique way, she cooperated by her obedience, faith, hope, and burning charity in the work of the Savior in restoring supernatural life to souls" (LG 61). Is it legitimate, thus, to say, that Mary is Co-redeemer? In certain contexts, this may be understood well by everyone, but that may not always be the case.
An analogy with the Eucharist can help us grasp the point. The presence of the priest is necessary for the celebration of Holy Mass, and without the priest, the sacramental actualization of Christ's sacrifice cannot take place. However, this does not mean that we cannot also say that the celebration belongs in some way to the entire liturgical assembly and to the Christian people present at the Eucharist, as all those present, by virtue of their common priesthood, collaborate with the ministerial action of the priest.
Similarly, we can say that Christ alone is the Redeemer, while the Church, united with Jesus in the Redemption, also collaborates in this task: the Church is thus co-redeemer. The disciples, too, collaborated with Christ in spreading the Gospel. They not only preached, but also performed miracles in his name. As St. Paul says, they were "God's collaborators" (1 Cor 3:9). This kind of collaboration can be attributed to the Church and rightly to Mary as well.
However, some may misinterpret the use of the title Co-redeemer, thinking that the prefix "co" implies that the Redemption is a joint work of Jesus and Mary. We believe that the Redemption is the work of Christ alone, as only He can accomplish it. In this sense, we should not say that Mary is co-redeemer, as she is not the source or origin from which the Redemption arises.
Some excerpts from Antonio Ducay
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