The laws shall be written in their heart and they will be my people is a promise kept. The message from Jesus is a revelation that men no longer obey the laws out of fear but indeed they themselves are the law and the laws live within them. Righteous people obey the laws naturally for they inherit that attribute from He who lives from the beginning. It is a genetic trait.
Jesus became the first of many when he was enlightened of the Kingdom through the word spoken by John. Having heard the word spoken by John Jesus became the living word and when he spoke the word many were awakened to the knowledge that indeed they were a people with the laws written in their heart. The words spoken by Jesus are a living force that begets understanding to those with ears to hear even now.
Jesus came not to change the law but to reveal how the law changed. No longer were the laws physically written in stone and placed in the ark but were instead written in the hearts (genes) of many becoming a living force made manifest through a desire to live the law. The old Ark of wood containing laws of stone was passed away and all who enter into the Kingdom become a new ark wherein the laws abide.
Either obedience of the law by nature or excused from the law by grace the law is the dominate factor to determine good from evil. Whether the law is written in a book or written in the heart obedience of the law will determine the destiny of the world.