Eamonn Conway, former head of theology and religious studies at Mary Immaculate College in Limeric, Ireland, wrote the following in an essay on the topic of Mary and her relationship tosacerdotaldotal priesthood in Catholicism:
[E]ach of the Marian dogmas, properly understood, reveals something of Mary’s uniqueness and at the same time the redemption to which each Christian is called through Christ.
So how and why is Mary special and unique? Karl Rahner’s exploration of the dogma of the Immaculate Conception can be a help to us here. Clearly, Mary is unique in being conceived without original sin. At the same time, this same grace is given to each Christian at Baptism. So there must be more. Rahner argues, to the dogma than the fact that Mary ‘was graced a little earlier, temporally speaking, that we were’ (through Baptism). The ‘more’ is that it was God’s plan that from the moment of her conception, Mary would play a constitutive part, an indispensable role, in salvation history. Through Mary, God’s promise of redemption is put into effect; the promise of redemption is rendered possible or the whole of humanity; through her, it literally takes flesh. Thus, Mary belongs to the very fabric, the structure of salvation history . . . Mary is a model of discipleship for us because she cooperated freely in God’s plan for her, as we also must do. However, in her case God’s plan saw her, a creature, being woven into the very fabric of salvation history. It is in this way that she is different from us, but not in having to struggle to accept and follow God’s will.
If we cooperate with God’s will, then we too participate in salvation history, but our participation is only possible because Mary played her part . . . Karl Rahner notes that:
Devotion to Mary, built into and included within the wholeness of the Christian life, is something essential for the Christian and particularly for the priest: something for which we can and should seek God’s grace, in order to really possess, cherish and maintain this living personal relationship to Mary the mother of the Lord and thus our mother also. (Eamonn Conway, “Mary’s Hymn of Praise” in Eamonn Conway, ed. Priesthood Today: Ministry in a Changing Church [Dublin: Veritas, 2013], pp. 213-222, here, 216-17, 218, 219, emphasis added)
As with the rest of the doctrines, dogmas, and practices affirmed by the modern Roman Catholic Church, such serves as further reason why Latter-day Saints should never be tempted to engage in theological ecumenism with Rome, let alone be tempted to join (or, for others, myself included, to return) to her ranks.
For a volume presenting the truth about the Mother of Jesus, see Behold the Mother of My Lord: Towards a Mormon Mariology.