kjv@1Kings:9:6@ But if ye shall at all turn from following me, ye or your children, and will not keep my commandments and my statutes which I have set before you, but go and serve other gods, and worship them:
Notice that it is the serving of other gods that God is primarily concerned with. People often say "I haven't sinned". I'd ask what other gods have you served. The trick is not to "believe in a god" it is to "believe the God" and to serve Him alone.
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