What is Christianity to you?

The Book of Romans, an epistle to the Church of Rome, by the Apostle Paul is said to be the most comprehensive guide to what Christianity is. I studied it and it really enlighten me. I realized that so many Christians do not know what it is. This is why they ride the pew Sunday after Sunday and offer nothing to the Church or society. This is why so many Christians live as the world lives, defeated. Tell me, "What is Christianity to you?"