In every way, Jesus was the one who came to do the will of the Father, to announce the presence of God's redemptive reign in history that establishes a new relationship between God and His people, and thus to enable us to live obediently. This is how He fulfills the Law and the prophets. He also tells us of the corresponding results of our actions of obedience or disobedience. Not even a little point on a Hebrew letter can be erased. Not even the movement of the pen that causes the little wings on letters will disappear.
Scripture is authority and the ethic proclaimed is that it is to be obeyed.
In fact, Jesus did obey the law to the letter, and, more importantly, demonstrated the heart behind the law, and that is what the Pharisees and Scribes simply failed to understand. If we are ever to understand the heart behind God's law, we must first have respect for the law. Let's illustrate that by thinking more about the disciples. Here are a bunch of guys who have made radical changes in their lives. They have come from a Jewish background and understanding of the law, and yet they left everything to follow Christ.