Idols are forbidden because nothing that we can make or that is found naturally in this world can adequately represent God. Only he knows what he is, and only he can tell us. It is not possible to represent perfect holiness, infinite wisdom, absolute goodness in an image. Any attempt to do so detracts from God’s perfection, and only hinders us from coming to him. His word is how we know him and we worship God by his Spirit as he opens our understanding to what is revealed in Scripture.
Scripture’s warnings are the means by which God preserves his elect who can never be lost, but those warnings need to be taken seriously in order to do their work.