Jesus was conceived by the Holy Spirit through the virgin Mary. Isaiah speaks of Virgin Mary 700 years before the birth of Jesus.

Isaiah 7:14

Therefore the Lord Himself will give you a sign: Behold, the virgin shall conceive and bear a Son, and shall call His name Immanuel.

Luke 1:28

The Angel Gabriel said to Mary, “Rejoice, highly favored one, the Lord is with you; blessed are you among women.”

Roman Catholics believe this passage points to the sinless nature of Mary. This belief was announced in 1854 in what Catholics refer to as Immaculate Conception. This was their answer to the question, how could Jesus Christ be born sinless if He was conceived inside of a sinful human female? The logic is that Jesus would have inherited the sinful nature from Mary. The Biblical solution to this problem is understanding that Jesus Himself was miraculously protected from being polluted by sin while He was inside Mary’s womb. A natural birth (from the act of sex) would bring forth the nature of sin. A supernatural birth through the power of the Holy Spirit (not a sexual act) would bring forth a sinless birth.  Mary’s genealogy in Luke 3 is traced back to Adam, so Mary had a sin nature. 

Romans 3:23

All have sinned and fall short of the glory of God.

Mary is not a mediatrix; a mediator between God and man. There is only one mediator, Jesus Christ.

1 Timothy 2:5

For there is one God and one Mediator between God and men, the Man Christ Jesus.

Mary made it clear that she was in need of a Savior. Only sinners need a Savior.

Luke 1:46

And Mary said: “My soul magnifies the Lord, And my spirit has rejoiced in God my Savior.”

It is common in Christianity to ask others to pray for you and to pray for others, but we shouldn’t be contacting the dead in Christ to pray for us. The Hail Mary is out of bounds for Protestant Christians. Christians pray to the Father, The Son and The Holy Spirit. Christians don't contact the dead or mediums; people who call on the dead. Roman Catholics don't believe they are worshiping Mary. This would be blasphemy. They pray to Mary, for her to intercede in prayer for them

Levitcus 19:31

Give no regard to mediums and familiar spirits; do not seek after them, to be defiled by them: I am the LORD your God.

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