The Father's redemptive plan didn't begin in a manger. While John's Gospel ignored many of the details of Christ's birth he made it clear that Jesus was from the beginning. His coming to earth was to accomplish, or finish, God's intention from creation. The manger signaled that the Kingdom was near.
One day there was an unlikely encounter between Jesus and a Samaritan woman. Their meeting took quite some time and resulted in many Samaritans, long opponents of the Jews, believing Jesus was the Messiah. His disciples were concerned for his physical well being and inquired about whether or not he had eaten. His response to them was another of the many verses in John's Gospel affirming that he had been sent by the Father. Jesus said---
My food is to do the will of Him who sent Me and to finish His work.
John 4:34, HCSB
His use of the term most often translated "food" is interesting. The broad translation means simply food, that which nourishes or sustains. A narrower use of the word was in Jewish dietary laws, meaning specifically the foods either allowed or prohibited in their strict system. Here, it is taken to mean that which spiritually satisfies or fulfills. Our Lord's nourishment was to do the Father's will and finish what had begun in creation.
Jesus emphasized both elements of this particular "sent" statement throughout his earthly ministry. His oneness with the Father, that he was sent by the Father, and that his words and works were those given by the Father are attested in forty-one separate verses from John 6 through John 17. These texts further amplify Jesus' submission to accomplish, complete, or finish the work the Father had assigned to him, in spite of their total rejection of him. John recorded his final words from the cross---
After this, when Jesus knew that everything was now accomplished that the
Scripture might be fulfilled, He said, “I’m thirsty!” A jar full of sour wine was
sitting there; so they fixed a sponge full of sour wine on hyssop and held it up to
His mouth. When Jesus had received the sour wine, He said, “It is finished!” Then
bowing His head, He gave up His spirit.
John 19:28-30, HCSB
Jesus was sent to give his life as a ransom for many (Matthew 20:28, Mark 10:45). His death finished God's plan to redeem mankind. He was the payment for our sin. Christmas celebrates his birth, the Incarnation, for the single purpose of serving as the sacrifice for our sin. He accomplished what none of us could.
But, there's more. We are currently in the season of Advent, the traditional period of anticipating his birth and his second coming. At a time only known by the Father, Jesus will finalize God's plan for humankind. it's a subject of great debate among Christians, the details of his final appearing, the Day of the Lord. Still, we mostly agree that he will establish a kingdom forever, a new heaven and a new earth, and that every knee will bow and tongue confess that Jesus is Lord. Christmas raises our awareness that this hour is near, and that we should approach it with great expectation.
Here's the Christmas bonus. He was sent to finish something else too. Everyday this one verse gives me chill bumps of expectancy, the thrilling reality that he's working in my life right now. Paul wrote it with an emphatic thrill---
And I am sure of this, that he who began a good work in you will bring it to
completion at the day of Jesus Christ.
Philippians 1:6, ESV
Christmas reminds me that Jesus was sent to do God's will and finish his work. Part of that work is what he is doing in me and you right now, in those chosen to perpetuate the faith and fulfill his purpose in our lives. Like the rambunctious little child, we're wearing the t-shirt emblazoned with the words He Isn't Finished with me Yet. But, there's this promise that the one who began this work in us will finish it.
Wondering what that will be, the finished work he is doing in us? Here's what John wrote---
Beloved, we are God’s children now, and what we will be has not yet appeared;
but we know that when he appears we shall be like him, because we shall see him
as he is. 1 John 3:2, ESV
O Come Let us Adore Him, indeed.