"I Believe in Jesus."
You are trapped in your house, surrounded by a wall of fire, and your doom is almost certain. Suddenly, out of nowhere, a fireman blast down a door and says "follow me outside!" In your relief you sit down and smile, because now you know who it is that came and made a way to safety.
Belief, or faith, or trust, was not understood this way in first century Palestine. When Jesus said, "Believe in me," it wasn't only a mental assent he was calling for, but a trust that brought about a new inner life, and therefore a new behavior.
This is an old argument that is regurgitated time and time again; and certainly there are much more learned men and women who have lent their voices and pens to this discussion. But I feel as if it is worth reiterating as often as possible.
The Christian faith is incarnational, if you will. It involves your flesh and blood, in addition to your mind. It won't due to simply maintain an awareness of Christ, or orthodox principles; one must also seek to become, through belief in Christ, the type of person who actually obeys the teachings of Christ. That is what it means to believe,