In Matthew 5:18, Jesus said that the Law will not pass away until all is accomplished. In light of your teaching that the Law no longer has authority over the believer, what did Jesus mean?
First, we assume you are following our Exodus study, but we want you listen to two specific lessons (Lessons 20A & 20B), if you haven't already.
To summarize his teaching in this lesson, Pastor Armstrong explained that all men, both Gentile and Jew, must meet the strict demands of God's Law if they are to enter into the Lord's presence. That standard is perfection (i.e., to keep the whole Law perfectly). Since no man can meet this standard apart from Christ, every man stands condemned for their sin.
Jesus lived a sinless life under the Law to satisfy the Law's requirements. When Jesus said the Law cannot pass away until all is accomplished, He was speaking about His role in accomplishing the Law on our behalf. Jesus died to pay the price required for sin under Law, though He had no sin of His own to pay. Now by our faith in His work, we are credited with Christ's perfect accomplishment of the Law. In this way, every believer is considered to have accomplished the Law on the basis of faith in Christ's work.
That is the full meaning Jesus' words when He told the Pharisees that the Law will not pass away until everything it requires has been accomplished. The Law exists to condemn men's sin, so until a person "keeps" the Law perfectly, the Law remains in effect to condemn him. Therefore, the Law can only "pass away" after it has been accomplished (or kept) perfectly. The only way a person can meet this standard is by faith in Jesus Christ's work.
At the time Jesus spoke these words, the Pharisees were claiming that Jesus taught men to ignore (or break) the Law, but Jesus denied their accusations. He said if someone was teaching that God's Law can be freely broken, they were not fit for (i.e., "they were least") in the kingdom. Obviously, the truth must be the opposite. Jesus was teaching that the requirements of the Law MUST be met, BUT we can't meet them in our own ability.
That's what Jesus meant when He said that our righteousness must exceed the Pharisees. The Pharisees were scrupulous at keeping the law (that is, breaking fewer laws than most). They were considered the highest example of righteousness in that culture. These men were incredibly pious, yet they even they failed to keep the Law perfectly, which is the requirement for anyone wishing to be approved by God through law-keeping.
So when Jesus said our righteousness must exceed the Pharisees, He was condemning the Pharisees (since even their extreme efforts to keep the Law weren't good enough), and He was declaring to us that attempting to be righteous through keeping law is a futile effort. The Law demands perfection, so if someone wants to enter Heaven by works of law, they must meet an impossible standard.
Therefore, when we attempt to "keep" the law in response to Matthew 5:18 (which is merely breaking fewer laws), we are actually doing the opposite of what Jesus was teaching. Jesus was speaking of Himself when He declared that all written in the Law must be accomplished. Jesus is the One Who accomplishes it all on our behalf, first in His perfect life, then in His sacrificial death on the cross and finally in fulfilling all prophecy concerning Israel.
Once again, the solution to this dilemma is not attempting to keep the Law ourselves (which will never produce righteousness), but rather we are credited with accomplishing all that the Law requires by faith in Jesus' work done on our behalf.