K
What you are forgetting is how powerful David was. The reason why is that David would ask God what to do. When David failed is when he did not ask but acted on His own. What does that tell us?
That is true and also where he failed is when he transgressed the law, but the thing David did do that is carried over under the new covenant is that when he did mess up he repented of what he did. Else wise he would have been held to the capital punishment carried by the Mosaic laws for committing murder and adultery....