This one is for Greg Jackson. May my blatant rejection of the Catholic Marian doctrines make you believe that I'm secretly a Catholic all the more.
Beyond these brute facts of Scripture and extra-scriptural doctrinal history, Mariolatry does not adhere to the logic of the faith (typus doctrinae, see 2 Tim 1:13). In other words, it is a negation of the biblical and reformational concept of sola gratia understood as divine favor and consequently lacks coherence with the other articles of the faith. We can observe that this is true in several ways. First, Mary declares in the Magnificent "my spirit rejoices in God my Savior" (Lk 1:47). If Mary did indeed rejoice in God as her savior, then logically we may infer that she needed a savior. But if she was not subject to original and actual sin, then this statement would be false. Furthermore, Scripture teaches that all persons are fallen. Paul (among others) asserts this several times (Rom 3:23 and numerous others) that "all have sinned." If that is so, then logically the predicate "all" (which Paul and the other New Testament writers qualify in relationship to Christ alone) would also apply to Mary.
Official Roman teaching is cognizant of this objection and has stated (echoing the reasoning of the fourteenth century theologian Duns Scotus) that preservation from original and actual sin constitutes being "redeemed in a more exalted fashion" by the merits of Christ. Nevertheless, this is not cogent reasoning in light of the fact that they are positing Mary as a concrete subject was never in her actual existence in need of a savior. Part of the difficult here appears to rest on assumption of their Realist (opposed to a Nominalist) ontology wherein Mary is caught up in and represents a universal of human nature which is subject to original sin, even if she as an individual is not. Nevertheless, if she, as the New Testament suggests (Mk 3:21, Lk 1:47, Jn 2:5) was simply an ordinary woman who was subject to the curse of original and actual sin, then she is the true model of the faithful Church of God. She is the sinner who is indwelt by God himself and justified by his "favor."
The second problem with the Marian doctrines from the Evangelical Lutheran perspective is the question of Enthusiasm. Just as the Pope and the Roman magesterium in general insists that it possess holiness and teaching authority on the basis of the Spirit apart from the Word, so too Mary gained her preservation from sin and therefore her redemption from the Immaculate Conception which happened apart from the Word. In Luke's account though, Mary trusts in the angel's Word that tells her that God is favorable to her (Lk 1:38). In connection with his rejection of Enthusiasm, Luther held that Mary had conceived through the hearing of the Word in faith. The text itself clearly vindicates this view. The conception occurred only because Mary believed the Word of God and gave her ascent to the explanation of the angel: "I am the Lord's servant," Mary answered. "May it be to me as you have said." Then the angel left her" (Lk 1:38, Emphasis added). As we have seen, this cannot be construed as being the meritorious cause of her conception, but rather is the proper response of faith to a divine promise by a sinful human being. It means that she as the model of the true Church which faithfully listens to God's Word and trusts in it.
Hence this also parallels the Roman Catholic/Evangelical Lutheran divide regarding teaching authority. Whereas the according to the Roman teaching, Mary possesses infallibility and perfection as a predicate of her being, so too does the Church and her magisterium. Truth and righteousness are predicates of the Church, given to it by the Spirit operating apart from the Word. Both the Church and Mary, in this conception, indeed receptive to what it comes to her from without (truth and grace), but this is obedience the result of an infused righteousness. By contrast, the Evangelical Lutheran claims that Church is always sinful and therefore must trust in an alien righteousness (iustitia aliena)external to it. It always needs God as "savior." Therefore the true Church, living the life of the vita passiva harkens to the Word of God and receives Christ in her inner being through unio mystica (Mk 3:34, Jn 14:23, Gal 2:20). This occurs through the external Word and the means of grace alone.