Christmas is a celebration of Christ. Though it is now known more for how it affects the economy than how it affects the soul, the foundation remains. Why was Jesus, the Christ, such a big deal?
Christ means "the anointed one". In the times leading up to Jesus' birth, kings were chosen and appointed by means of anointing them with oil - putting oil on their heads. It set them apart as royalty, and identified them as men with a purpose. Once they were anointed, they were set apart as having a job to do.
So what was Jesus' job? Matthew, a disciple of Jesus who later wrote an account of Jesus' life, recorded the words of the Angel who gave instructions to Jesus' adopted father, Joseph: "She will give birth to a son, and you are to give him the name Jesus, because he will save his people from their sins." Jesus means "God with us". God chose to be with us in order to save his people from their sins.
Why do we need saving from our sins? What is so bad about a little sin, after all - everyone has some, nobody is perfect, right? Exactly right- nobody is perfect, and our common recognition of the fact demonstrates that a standard of perfection exists. We cannot recognize "un-perfect" unless we have some idea of what perfect is. God, our creator, is that standard of perfection. It is only hard for us to understand how God can condemn sin when we use our human standard. If we look at it from God's standard it makes a lot more sense:
God made the world for one purpose: to glorify himself. Basically, everything is by God, for God, and to God - the Bible says that live and move and have our being in Christ. Without God, we don't exist. From that perspective, it makes sense that my purpose is to live for God and do what He wants. It may not be easy, but it makes sense.
However, all of us have chosen to live for ourselves rather than for God. All of us have fallen short of God's standard, we have missed the mark. We have not done what God made us for. Rather than seeking out fellowship with God, we have turned from God. We are faulty creations, failing in our purpose. Because of that, God has every reason to punish us with hell.
That is the position all of us are in: faulty creations, deserving Hell. If we are left to ourselves, we will go to Hell. We can never get right with God on our own. It is only from this perspective, looking up from the pit of Hell, that Christ and Christmas can be properly seen.
Christ came to save us from our sins - and from the eternal damnation which is the consequence for failing to live up to God's standards. He did it to glorify God the Father.
Jesus says "I am the way, and the truth, and the life, no one comes to Father except through me." Jesus is, in one way, very exclusive - He is saying there is no other way to God except through faith in Himself. In another way, He is incredible inclusive. He says:
"Come, all you who are thirsty, come to the waters; and you who have no money, come, buy and eat! Come, buy wine and milk without money and without cost."
This is what Christ and Christianity are about: grace. Grace is graphic, shocking, and unfair. Grace is forgiving someone who is guilty of a terrible crime. If you want to immerse yourself in a very readable and profound book on Grace, read "What's So Amazing about Grace" by Philip Yancey. That book has these words: we're all bastards but God loves us anyway. The Bible says similarly "while we were yet sinners, Christ died for us." Salvation is for bastards: if you're one (like me), recognize it and accept the Grace that God extends you in Jesus. Forgiveness of sins, Christ in you, the hope of Glory. Many have died for that hope, for the sake of his name. Their blood tells the story more powerfully than I can: they have found something worth dying for.
Jesus had something he was willing to die for: the glory of God the Father. That is why He came, that is why Christmas happened. Christmas is for bastards.
This is no sensationalism, intended to make the gospel seem more radical than it is. We will never fully grasp just how phenomenal the gospel is - but we get closer and closer as we more fully realize just how bad we are.