But today, this definition is not necessarily the meaning of "Christian" any more than the definition of "student" is someone who willing desires to learn and grow in knowledge through study and discipline. How many students can you think of that went (or are presently going) to school only to party all night and miss classes all day? How many students like being in college for the social aspects. How many Christians do you know that identify with Christianity as a social club, but either don't believe that Jesus is who he claimed he was, or don't understand the gospel enough to make a decision either way? And what of the groups that insist in calling themselves Christian but profess doctrine that is clearly not inline with the Bible, like the LDS? Or how about those "Christians" that show little or no life evidence of faith? You may know someone like this. Or what about a "Christian" church like the Westboro Baptist Church?
When I think about this, John 6:47-66 comes to mind. In this passage, Jesus explains that he is the bread of life. Using graphic symbolism, Jesus teaches that those who eat his flesh and drink his blood will have eternal life. Misunderstanding, many of the disciples question this teaching, really struggling with Jesus' instruction. And John 6:66 says, "After this, many disciples turned back and no longer walked with him" (ESV). Here Jesus had many followers hanging on his every word. He had just fed thousands. Yet an earlier passage in chapter 6 tells us that they were only in it for the miracles. They wanted to see amazing things or be healed. Some were just hanging around for the entertainment. So it is with some "Christians" today.
It could be that there are some "Christians" sitting next to you in church that are not believers in Christ. Many people on Facebook claim "Christian" as their faith but clearly don't believe the doctrines of Christ. Many wear crosses but do not know the God-man who died on one for them. And there are those that see Christianity as a moral code or way of life, an ethic or politic.
I remember recently reading a man calling himself a Christian who claimed that the there was no intelligent designer of the earth of life, that life and all things are just a chance happenstance, and that God has no influence over creation (because it was not his creation in the first place). I'm not sure how that position can fit within Christian teaching because it can't. It just can't. I know of people that call themselves Christians but deny that Jesus is exclusively the way to heaven, something Jesus himself clearly taught.
Therefore, we must take caution when assuming the meaning of the word, "Christian." Christian originally was not an adjective, like Christian music or Christian books; it was a person who held a confession in Christ. However, today, it is really a self-identified membership into a social identity. There are some that are trying to avoid using the word all together, often substituting it with "Christ-follower," but this doesn't really change anything. And there are some who are diligently trying to reclaim the meaning of the word, but Webster's doesn't have word police. So what we really ought to do is keep in mind what a Christian is or is not. We should bear in mind that a person calling him or herself a Christian may be an ambassador for Christ's Kingdom, or not.