On December 8, the Catholic Church celebrated the Solemnity of the Immaculate Conception of Mary. Note that this does not refer to the conception of Jesus in Mary, i.e. the virgin birth. This dogma is a belief of how Mary was conceived in her mother’s womb.
The Catholic Church believes in the “Immaculate Conception” of Mary, wherein she is considered unstained from original sin and actual sin. This is not explicitly told in Scripture, but there are several passages that hint it and support this doctrine. Consider this scripture passage:
[Genesis 3:15] I will put enmity between you and the woman, and between your seed and her seed; he shall bruise your head, and you shall bruise his heel.”
The context is after Adam and Eve have sinned and God is punishing the snake. This passage is often spoken as being the protoevangelium or “first gospel” because it is a prophecy concerning Jesus. This “seed” of the woman is Jesus, because he will “bruise” the head of the snake (who represents Satan). Now this “woman” must be Mary as it is her “seed” that is Jesus, since she is his mother.
Now, knowing that the passage refers to Jesus and thus to Mary, we see that God declares there will be an “enmity” between the snake (Satan) and Mary. The word “enmity” can mean “separation” or “total opposition”. Thus we see that Mary will be separated from Satan and sin and will be in total opposition to Satan.
Now consider the following verse:
[Luke 1:28] “Hail, full of grace, the Lord is with you”
The context of this is where the angel Gabriel greets Mary at the annunciation of Christ. The phrase “full of grace” is translated from Greek word kecharitomene. Now, grace is the very life of God, his Love. So, in other words, Mary is full of God’s love and life. We know that sin is the absence of grace. Therefore, if Mary is full of grace, that means that she is without sin, in opposition with evil.
Protestants will object to this elevation of Mary; that all sin except for Christ. However, this is a fitting doctrine in that it says something about her son Jesus Christ, namely, that she was to be a pure vessel for his incarnation.