12/22/2013 09:52 am ET Updated Feb 21, 2014


Today is the fourth Sunday of Advent, and the Advent season officially ends and Christmas officially begins in the evening of this coming Tuesday, December 24, Christmas Eve. What we have been waiting and preparing for during the Advent season is, at last, close at hand.

Last week we briefly mentioned the incarnation. This is the primary focus of Christmas, so this week we need to look in detail at the Christian doctrine of the Incarnation. The Incarnation deals with the fact that Jesus is the union of divinity with humanity, that Jesus the Christ is fully God and fully human, and that Christmas is the celebration of God's becoming flesh and blood while also remaining God. [Origin of Incarnation traced to Latin: incarnari, "to be made flesh."]

This is the second part of the doctrine of the Trinity: God the Father, God the Son, and God the Holy Spirit. The doctrine of the Trinity is easier to understand when we think of the three basic activities of God.

The first story in the Holy Bible deals with God creating from nothing everything that is, the earth and all living plants and creatures, including man and woman. People may argue about the origin of things as described in "Genesis," but that is what is taught in the very beginning of "Genesis." This is the first part of the Trinity -- God's action as the creator or God as the Father.

The birth of Jesus is the second part of the Trinity. Christmas deals with the act of God's offering salvation to humankind through the person of Jesus. The birth of Jesus, a real, honest-to-goodness human, is the act of God's coming to earth in human form to live and dwell with human creatures in order to provide them with a way of salvation. This is the miracle of the Virgin Birth -- God's action as the savior through the person of Jesus, his Son. Hence, in Christmas we have the second part of the Trinity -- God the Son.

The third part of the Trinity -- God the Holy Ghost or Holy Spirit -- takes center stage with the celebration of Pentecost, which focuses on the descent of the Holy Spirit and is celebrated on the fiftieth day after Easter. So we'll put off taking an in-depth look at God the Holy Spirit until closer to June 8, the date of Pentecost 2014.

Now back to Christmas. This is a time to spread joy and good cheer as you would at any birthday party. But this birthday party is not typical. The birthday party for Jesus is a twelve-day celebration, beginning on Christmas Eve and ending on the evening of January 5. Some people will begin the celebration of Christmas late afternoon or early evening on Christmas Eve by attending a worship service, while others will wait for an 11:00 p.m. Christmas Eve service, which traditionally ends at midnight with the singing of "Joy to the World." And many families will have their own worship service at home in front of their fireplace, with a celebration of the traditional Yule Log. And many people will join with others in going Christmas caroling.

It really doesn't matter how we celebrate Christmas, as long as our celebration has as its central focus expressing gratitude for God's love and on doing things for others and making them happy as Jesus has focused on doing for us. Christmas means doing special things for others, including giving gifts. When we celebrate Christmas we need to remember the words of Jesus in Matthew 25:35-36, 40: "I was hungry and you gave me food, I was thirsty and you gave me drink, I was a stranger and you welcomed me, I was sick and you visited me, I was in prison and you came to me ... Truly, I say to you, as you did it to one of the least of these my brethren you did it to me." (Revised Standard Version) So going out of your way to do things for others, including members of your own family, is going out of our way to honor Jesus during the 12-day celebration of his birthday.

The birthday party of Jesus should be one of great joy and good cheer. It should be a celebration of gratitude to God for joining us human creatures in the person of Jesus. It should be a celebration that focuses on what the angels said to the shepherds in the field near Bethlehem the night Jesus was born: "Glory to God in the highest, and on earth peace among men with whom he is pleased!" (Luke 2:14, RSV) We should always keep as central to our celebration that this is the birthday of Jesus, and the celebration of his birth should not be all about what makes us happy, but should focus on making our guest of honor happy.

Christmas is all about the birthday of Jesus -- all about God the Son. As John puts it: "In the beginning was the Word and the Word was with God, and the Word was God ... And the Word became flesh and dwelt among us, full of grace and truth; we have beheld his glory as the only Son from the Father." (John 1:1, 14, RSV)

So as we celebrate Christmas, may we remember the significance of the Incarnation and the second part of the Trinity -- what Christmas is really all about. And let our celebration of nearly two weeks truly glorifying God the Son.

May you, your family, and your friends have a very Merry Christmas!