Have you ever held a newborn baby? If you have, you realize how helpless they are. Yet this prophesy said that Messiah comes as a child. This, of course, came true at the birth of Jesus. This helpless child would grow up and be the Savior. Thus, this Messiah would save all those who place their faith in Him.
Isaiah 7:14All right then, the Lord himself will give you the sign. Look! The virgin will conceive a child! She will give birth to a son and will call him Immanuel (which means ‘God is with us’). The God we worship is not far away as pagan gods are often described but He is truly, Immanuel, or “God with us.” Isaiah goes on to tell us more about this child to be born. Isaiah 9:6For a child is born to us, a son is given to us. The government will rest on his shoulders. And he will be called: Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. 
The Messiah’s Birth is Announced by Angels from Heaven
Luke 2:15 When the angels had returned to heaven, the shepherds said to each other, “Let’s go to Bethlehem! Let’s see this thing that has happened, which the Lord has told us about.” 16 They hurried to the village and found Mary and Joseph. And there was the baby, lying in the manger.
Can you imagine how Joseph and Mary must have looked at their child who had been announced supernaturally? They would name the child Jesus just as the angel had instructed them. His birth was announced, not to royalty, but to ordinary shepherds who were now coming to see Jesus.
How excited they must have been to tell Mary and Joseph about the angels who told them of the birth. What was their first impression when they looked at baby Jesus who the angel said was the Messiah? Luke2: 11 The Savior—yes, the Messiah, the Lord—has been born today in Bethlehem, the city of David! 
The Messiah Would be the Bridge Between God and Man
Jesus is like no other person to come into the world. He was fully human and fully divine at the same time. Only Jesus could reconcile the Father in heaven with humankind. Jesus is the bridge by which God comes to earth and people come to heaven.
Colossians 1:19For God in all his fullness was pleased to live in Christ, 20 and through him God reconciled everything to himself. He made peace with everything in heaven and on earth by means of Christ’s blood on the cross.  Jesus came to save you! Have you placed your faith in Him yet?
Lord Jesus, for too long I’ve kept you out of my life. I know that I am a sinner and that I cannot save myself. No longer will I close the door when I hear you knocking. By faith I gratefully receive your gift of salvation. I am ready to trust you as my Lord and Savior. Thank you, Lord Jesus, for coming to earth. I believe you are the Son of God who died on the cross for my sins and rose from the dead on the third day. Thank you for bearing my sins and giving me the gift of eternal life. I believe your words are true. Come into my heart, Lord Jesus, and be my Savior. Amen. 
To hear how Messiah comes as a child, listen here:
[1-5] Tyndale House Publishers. (2015). Holy Bible: New Living Translation. Carol Stream, IL: Tyndale House Publishers.