Why the Law then? It was added because of transgressions, having been ordained through angels by the agency of a mediator, until the seed would come to whom the promise had been made.Galatians 3:19(NASB)
The Law was given to Moses through God's angelic agents, 430 years after the Lord had made His covenant with Abraham, promising blessing and redemption through his Seed. The Law was not given to annul, supplement, or alter this unconditional Abrahamic promise and so the question arose among many Jewish believers in the early Church: "Why was the Law given, what was the purpose of the Law, and did it alter the terms of the Abrahamic promise?"
Paul explained that when man sinned against God, all humanity was imputed with a sin nature. But man did not recognise the wickedness of sin in his own life until the Law was given to Israel. It was necessary for Paul to explain the purpose and character of the Law and to show how it did not alter, in any way, the covenant made with Abraham, but rather complemented it in a most unusual way.
The Law demanded perfect righteousness and so it exposed the wicked sinfulness of man. The righteousness requirements of the Law were not given as a means of salvation, for its standard is unattainable... so much so that no man living could ever be justified by it. God, in His wisdom, knew that sinful man would always fall short of the perfect standard that His holy Law demanded. Indeed, the righteous requirement of the Law identified the gross sinfulness of man - in order to show people that they needed someone to save them from their sins - for they could never be justified in the eyes of God by their own merit. All fall short of the standard laid out in the Law.
They could never come up to the high standard that the Law of God required of them and so Paul set about to answer the question: "Why the Law then?" And goes on to explain, "It was added because of transgressions - and it was added until the Seed, (Whom Paul identified as the Lord Jesus Christ) to Whom this promise had been made, had come."
Paul explained that the Law was like a tutor, an instructor, a teacher who takes a child by the hand and leads them to a right conclusion. The Law is to show us that we are all sinners in need of a Saviour. The purpose of the Law is to lead us to Christ by showing how deeply we are embroiled in sin and how desperately we need a Saviour. The unattainably high standard of the Law is to show that we can't possibly become justified by keeping the Law, but are under its curse as well as being under the sentence of death. Indeed, Paul further likens the Law to a jailer because its impossible standard has shut all men unto sin... and the wages of sin is death.
The Law shows that we are all sinners and that we all need a Saviour, for there is none that are righteous, not even one. The Law is not contrary to the promise that God gave to Abraham - for the Abrahamic covenant still stands, and Paul further explained how long the Law was to be implemented: from the time it was given to Moses until the Seed (Jesus Christ the righteous) was sent. "The Law was given to Moses until the Seed would come, to Whom the promise had been made."
Jesus died in our place to pay the incalculable price that the Law demands from each of us. Jesus took the punishment that the Law passes on all who fail to live by it and He became a curse in place of us. Jesus was made sin in our place and Jesus died in our stead, for the wages of sin is death. Jesus died as our sin-substitute. He not only died FOR our sin but He died UNTO sin. He not only paid the PENALTY for our sin but He also broke the POWER that sin, death, Satan, the flesh, and the Law have in our lives. Just as He identified with our sin and death, so we are identified with His righteousness and life, by faith.
When Christ DIED we died IN HIM - so that death no longer has dominion over us - and neither does the Law.
Heavenly Father, thank You that Christ was placed under the sentence of death that the Law required on my account. And thank You that He also died unto sin so that I am released from the judicial sentence that the Law has passed on me. In Christ I am dead to sin and dead to the Law, and in Him I have been raised into newness of life and clothed in His righteousness. In Jesus' name, AMEN.