God is a God of mystery and surprise. Who could have ever thought that He would call upon a young teenage girl to bring His Son into the world? Well, actually Isaiah had prophesied in 7:14, “Therefore the Lord will give you a sign. The virgin will be with child and will give birth to a son, and will call him Immanuel.” When God chooses Mary for the task He is doing what is seemingly impossible to show that Jesus really is the unique Son of God. Nothing is impossible with God.