For I say unto you, That except your righteousness shall exceed the righteousness of the scribes and Pharisees, ye shall in no case enter into the kingdom of heaven
Matthew 5:20
Matthew chapters five through seven record the longest, most life-changing sermon ever preached, the Sermon on the Mount. This verse is the key to Jesus' message. Only Jesus knew what was about to happen, not just to Himself on the cross but to His followers in their living and worship. Because of His death , Jesus' followers would not just be saved but changed. No longer would a book of rules guide their behaviors. After the cross, the indwelling Holy Spirit with His grace would be their Guide and Teacher.
Worship would also change. Moving from law to grace meant we would be moving from rituals to reverence, from print to passion, from sacrifices of animals to sacrifices of the heart, and from God's demands to our desires. Worship to God by grace would be infinitely more meaningful to us and to God than legal worship could ever be.
Yet, there was one thing Jesus wanted us to know. Grace always exceeds the law. That becomes evident in our salvation, The books of Romans, Galatians, and Hebrews will tell us that grace GIVES us more in salvation than the law ever could. But here, Jesus was telling us that grace also EXPECTS more than the law ever expected.
The remainder of Jesus' sermon illustrated that truth. Where the law expected its followers not to murder, grace expects its followers not to even be unduly angry (Matt 5:21-22). Where the law expected its followers not to commit adultery, grace expects its followers not to even lust (Matt 5:27-28). And where the law expected its followers to do harm only to those who deserved it, grace expects its followers to turn the other cheek (Matt 5:38-39).
Some in the church are quick to boast of their freedom from the law, as though that freedom has given them the right to behave anyway they wish; but they are wrong. Grace does not expect less of us than the law. Grace expects more-far more. Grace has RAISED not LOWERED the standard of our righteousness. Jesus' stern warning should make us all realize that the call of grace is a call to the highest holiness.