Christianity is many things. It is a religion, in the best sense of the word, and it is a relationship with God. It is an ethical and doctrinal system that teaches us how to live and what we must believe if we would faithfully follow Christ. But more than all of these Christianity is Christ.
All earnest inquiry into Christianity should begin with an inquiry into the person of the man Jesus of Nazareth. Who was this historic person? And if he was raised on the third day, as true Christians believe, who and where is he today? And what difference does this really make?
The crucial question, so it seems to me, is very simple: Was the carpenter of Nazareth really the Son of God?
John R. Stott suggests that there are two good reasons why all inquiry into Christianity should begin here. First, Christianity is Christ. The person and work of Christ are the foundation for all that the Christian religion has been built upon. This is true of Islam, in the sense that it is built on Mohammad, yet the prophet never claimed the things for himself that Jesus did. If Mohammad is a false prophet then Islam would still not be totally wrong. But if Jesus is a false teacher Christianity is a charade, a false religion built upon a false foundation. Stott says, "Take Christ from Christianity, and you disembowel it; there is practically nothing left."
It still baffles me that so many who do not believe that Jesus is the Son of God still remain convinced that Christianity is a great religion. "Jesus is a great man," they tell us. But he claimed so much more than this for himself. The philosophy he taught and the ethics he shared are not the primary issue with Jesus. The primary issue is Jesus himself. Liberal Christianity failed because it wanted to strip the Jesus of the Scripture and the Creeds from his supernatural actions and his divine nature and still keep Jesus in some sense.
The second reason why Christianity is about Jesus is that Jesus is the ANSWER to all important questions. If he is who he said he was then the existence of God is proven. Questions about our duty and our destiny, about life's meaning and what follows death are answered. And the purpose of divine revelation is also plainly answered.
If you are not a Christian you should make it your goal to gain a deeper understanding of who this man was and is. If he is the God-man then you will find that your most important questions will be answered, or at least have potentially credible answers that you can rest your life upon. If he is not the God-man then find some faith that doesn't make so many demands and claims upon your life and get on with it.