The Doctrines of Mary are very strongly debated. The only reasons she is not ridiculed against and looked down as is because there is not enough Biblical support about the doctrines. They don't contradict the Bible. The very early church (before 200 A.D.) believed and practiced these doctrines at least in a basic form. Immaculate Conception, Mother of God, Perpetual Virginity, Assumption, Mediatrix and Co-redemptrix, Devotion to Mary, New Eve, Mother of the Church, Queen of Heaven, and Immaculate Heart are 10 of the Doctrines of Mary that are constantly debated.
The doctrine about the Immaculate Conception is, according to the Catechism of the Catholic Church, Mary was "redeemed from the moment of her conception" and she was "preserved immune from all stain of original sin." By God's grace, Mary was given the grace of being free from original sin which was lost to the human race by Adam and Eve's transgression.
This special grace "comes from Christ." Some common misunderstandings about the Immaculate Conception teaching are that Mary is deity, that Mary is the source of her sinlessness, and that this contradicts the passage that all have sinned.
Mother of God is the easiest of the doctrines to explain. It states that Jesus is God, Mary is the mother of Jesus, and Therefore, Mary is the mother of God. Since Jesus is God and took on human nature from Mary's human flesh, she is the Mother of God in a physical way. To deny Mary as the mother of God is to deny that the fleshly nature of Jesus was God just as much as His Divine nature.
Perpetual Virginity is the doctrine that states that Mary was a virgin for her whole life. Mary only had one son, and his name was Jesus. Many people misinterpret the...