There was a true conservatism shown by Jesus in his claim not to destroy the law but to fulfill it. The law was spiritual, was holy, just and good, but the people, the world, had not reached this higher meaning: he led them to it.
He also fulfilled the law of love. There was one given by Moses in the Levitical code, and he gave the spiritual fulfillment of that as well as the others.
In the Sermon on the Mount he gave the spiritual meaning of various parts of the moral law. His formula for many of his expositions was, "Ye have heard it said by them of old time"; but he rejoined upon his own authority, "But I say unto you," thou shalt have no anger, lustful thought, revenge or hate.
