On December 8, 1854, Pope Pius IX released the encyclical Ineffabilis Deus, which declared the immaculate conception of Mary. Here is the heart of what the encyclical affirms (emphasis mine):
We declare, pronounce, and define that the doctrine which holds that the most Blessed Virgin Mary, in the first instance of her conception, by a singular grace and privilege granted by Almighty God, in view of the merits of Jesus Christ, the Savior of the human race, was preserved free from all stain of original sin, is a doctrine revealed by God and therefore to be believed firmly and constantly by all the faithful.
Hence, if anyone shall dare — which God forbid! — to think otherwise than as has been defined by us, let him know and understand that he is condemned by his own judgment; that he has suffered shipwreck in the faith; that he has separated from the unity of the Church; and that, furthermore, by his own action he incurs the penalties established by law if he should are to express in words or writing or by any other outward means the errors he think in his heart.
In this encyclical, the Roman Catholic Church claims Mary was “in the first instance of her conception . . preserved free from all stain of original sin.” That is, Mary was born without sin. Furthermore, the RCC also claims Mary remained sinless her entire life. Because of her sinless state, she was the “perfect” person to bear the Christ-child and to be the mother of Jesus. For those who believe differently, the RCC pronounces a judgment on them: “he is condemned by his own judgment; that he has suffered shipwreck in the faith.”
Protestants, more generally, and Evangelicals, more specifically, do not believe Mary was conceived apart from the stain of original sin. They affirm Mary was sinful like the rest of humanity. But they also affirm the virginal conception, a belief which affirms Mary was a virgin who conceived Jesus supernaturally by the Holy Spirit, not by a sexual union with a man (cf. Matt. 1:18-25; Lk. 1:34-35). This means we affirm the miraculous virginal conception, not the immaculate conception.
Because Evangelicals are often much better at responding to a wrong belief than affirming what they do believe, or due to the fear of being associated with a wrong belief, they have tended to shy away from affirming truth that ought to be affirmed. It is true Mary is not without sin, or, stating it another way, Mary is sinful and needs to be saved, which she acknowledges in referring to “God my Savior” (Lk. 1:47). By making this statement, even though the RCC may pronounce condemnation on us, or claim we have shipwrecked the faith, that is not true. Instead, we have affirmed God’s truth as revealed in the Scriptures.
But we have not gone as far as we can or should by leaving it there. Mary is, indeed, considered the mother of God (theotokos), not just the mother of Jesus Christ (christotokos). (This was answered at the Council of Ephesus in 431.) She played a special, unique and non-repeatable role as the mother of the God-man, Jesus Christ. Mary served a special role in redemptive history. This does not make her sinless, but special. And what made her this way is God’s grace, his favor that rested on her (Lk. 1:28, 30). Additionally, Mary serves as a model of humble piety, of one who lovingly trusts and serves the Lord, evidenced in her acknowledgment, “Behold, I am the servant of the Lord; let it be to me according to your word” (Lk. 1:38).
At this time of year we give thanks to God for sending his Son Jesus Christ to save us from our sins (Matt. 1:21). We also thank God for Mary and the role she played in redemptive history, and his grace and mercy shown to her as the mother of God. Finally, we learn from her as one who recognized her role as a servant and humbly and joyfully submitted her will to the will and word of the Lord. As we ponder Mary and the role she played in redemptive history as God’s humble, trusting servant, we recall “those who spoke to you the word of God. Consider the outcome of their way of life, and imitate their faith” (Heb. 13:7).