Ineffectiveness of the Law
Summary: The Law of Moses did exactly what God intended by making man aware of sin and its consequences, yet there were things it could never do.
Because the law of Moses made people conscious of their sin, no one could ever be declared righteous before God by doing what it requires. (Rom 3:20; Gal 2:16) In fact, if righteousness could be gained through the law, then there was no reason for Jesus to die. (Gal 2:21) Although the law included sacrifices to temporarily postpone people’s guilt for their sin, those sacrifices could never cleanse them of their sin. (Heb 10:1) As a result, the law could never clear their consciences, but continually reminded them of sin and left them with a sense of guilt. (Heb 9:9; 10:3-4)
The law could never give life or make anyone perfect. (Gal 3:21; Heb 7:19) Instead, it was a ministry of death because it made people guilty and condemned them of sin but could not redeem them from it. (2 Co 3:7, 9) As a result, everyone who depended on observing the law was in reality under a curse because it was impossible to do everything the law required. (Gal 3:10)
Though the law was perfect because it did everything God intended, it was weak, useless or ineffective because it made nothing perfect. (Heb 7:18-19) The law defined the terms or requirements of God’s original covenant with Israel and it clearly proved that no one could meet those requirements through their own efforts, so God declared the entire covenant obsolete. (Heb 8:7, 13) It was an external or outward covenant — unable to change a person’s nature — and only applied until a better one could be established. (Heb 9:10) The law of the first covenant was only a shadow or dim preview of the good things that would come under the new covenant, not the reality of them. (Heb 10:1)
Consider an analogy. Suppose a very good friend knows you need a house, so he gives you a copy of drawings or house plans for a new house and then builds it for you. The house plans are only a graphical representation of the real house and only suggest what the house will look like. Once you move into the house, it would be foolish to keep reviewing the house plans and trying to imagine what the house is like.
The original covenant with Israel, including its law, was a hint, suggestion or dim preview of the new covenant that would replace it. Not only do you have absolutely no need for the old covenant and its ineffective law once you have the new covenant, focusing on its requirements actually distracts you from the reality it predicted.