Because man does not know himself after the fall, God was forced to insert the law of God . That means something that was not originally intended was added afterwards.
God had to add the law in order to expose man and let man see his true fallen condition. Fallen man needed a true picture of himself. And the law of God was given to help man ascertain the true nature of his fallen sinful condition.
Today some people who have cancer are told to drink a certain kind of liquid which shows up under that X-Ray machine. This liquid helps to highlight the cancer that is growing inside of the cancer patient. This is somewhat of an anology of one aspect of the law of God. It is good and holy and spiritual. Yet it has a negative function as well. That is to expose the desease of sin eating away at the fallen mankind.
Man fell into rebellion against God and thinks that it is only a minor problem. In essence God says "You think that this is only a little problem that you can correct with not much difficulty? Here, this is My law. Keep this law."
The utter failure of man to keep the law of God exposes the true condition of the fallen mankind.
Edited by jaywill, : No reason given.
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