It seems too many Christians think that God’s Old Testament Law is impossible to keep, and that is the reason (they presume) it has been made obsolete. The assumption is that keeping it perfectly would result in one’s salvation, and since no one can keep it perfectly, an alternative (Jesus) was needed instead.
I have argued earlier that God’s law is indeed possible to keep, and there are people on record (both Old and New Testaments) who have done it. Yet even the people who were blameless in the God’s Law still needed His salvation. So even though it is possible to perfectly keep the law (some have done it) it will not merit salvation. Roman’s 3:20a states that no human will be justified by the works of the God’s Law.
This begs the question: What then is the Law’s purpose? The answer is in the second part of the verse: so that we will have knowledge of our sin.
So I think the better the Law is kept, the more we become aware of how much we need to be saved from certain spiritual death. That is why those who keep it best are the most humble. The process of following God’s Law uncovers the heart’s corruption; it dispels Satan’s deception that being good is good enough. But observing the Law perfectly does not change a person’s sinful nature, and that is the “fault” (Heb. 8:7, ESV) in the Old Testament Law.
But when we come to see Jesus as see a man of pure heart, upright nobility and fierce love; when we come to see him as perfect King strong in arm, violent in conflict and gentle to faint hearted; when we come to see this man willingly stripped, tortured and executed so we can escape our fate; and when we hear that he resurrected from death – and believe it, this does change our nature. It creates in us a desire to know Him who would go to such length to be with us. It creates a reciprocal love in our heart, and a willingness to be different and new. It gives us the will to invite the Holy Spirit in so we can be changed and made new. It’s like the sulfur on the tip of a match that ignites a flame. While in the body our sinful nature will still remain, but it suffers a death sentence and we are given a new will to resist our carnal nature.
This is why it would be fatal to dismiss the Old Testament Law as obsolete. It is good for more than just teaching and learning. It acts as a sword that cuts into our conscience, making us painfully aware of our desperate condition and need of a savior. Without this conviction Jesus would be nothing more to us than a dying man. His resurrection would be dismissed as a fable.