The virgin birth of Jesus Christ was necessary because of Original Sin that passed upon
the human race through Adam, Being born of a virgin, he never inherited original sin, and therefore was able to offer himself up as a sin offering for all of mankind.

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Isaiah 7:14   Therefore, the Lord himself shall give you a sign; behold, a virgin shall
conceive, and bear a Son and shall call his name Emmanuel.

Matthew 1:18   Now the birth of Jesus Christ was on this wise: when as his mother
Mary was espoused to Joseph, before they came together, she was found with child of
the Holy Ghost.

Matthew 1:23   Behold, a virgin shall be with child and shall bring forth a son, and
they shall call his name, Emmanuel, which being interpreted is, God with us.

Luke 1:26, 27, 31, 34, 35   And in the sixth month the angel Gabriel was sent from God
unto the city of Galilee, named Nazareth.
Vs.27   To a virgin espoused to a man whose name was Joseph, of the house of David;
and the virgins name was Mary.
Vs.31   An behold, thou shalt conceive in thy womb, and bring forth a Son, and shalt
call his name Jesus.
Vs.34   Then said Mary unto the angel, how shall this be, seeing I know not a man?
Vs.35   And the angel answered and said unto her, the Holy Ghost shall come upon thee,
and the power of the Highest shall overshadow thee; therefore also that holy thing which
shall be born of thee shall be called the Son of God.

Hebrews 10:5   Wherefore when he cometh into the world, he saith, sacrifice and
offering thou wouldest not, but a body hast thou prepared me.

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