Bluefalcon said:
I think believing in God in the Bible is always indicated by a change in one's actions, attitudes and motives. Faith that doesn't produce works really is dead. On the other hand, flesh-driven "good" works without faith in Jesus are devilish and lead many straight to hell. We are saved by grace through faith (that evidences itself in our actions, attitudes and motives).
Sometimes we seem to focus too much on what we think outward works should be from a Christian that we judge people's salvation based on what we think we should see in their works. Realize that there are multiple verses that one is saved by believing on the name of Jesus...period.
Realize that one can grieve or quench the Holy Spirit. Faith without works is dead because if one believes that he should do good works and he doesn't do them, it shows that his faith is useless for the cause of Christ.
Belief in Jesus is not a work because it is ingrained into one's being. Upon hearing the Gospel or however the belief came about it came without needing to earn it. If one hears the truth one may not want to believe it, yet it makes too much sense to resist. One may struggle with wanting to believe it, yet believes it anyways.
Try convincing yourself not to believe in Jesus. Can you do it or is it irresistibly ingrained into your logic so that you cannot get rid of it?