Matt. 5:17-18: "Do not think that I have come to abolish the law or the prophets. I have come not to abolish but to fulfill. Amen, I say to you, until heaven and earth pass away, not the smallest letter or the smallest part of a letter will pass from the law, until all things have taken place." NAB.

Nevertheless, Jesus does change the law. For example in Deuteronomy 19:21 it says: "Do not look on such a man with pity. Life for life, eye for eye, tooth for tooth, hand for hand, and foot for foot! " NAB. See, Leviticus 24:19-21. But Jesus says in Matt 5:38-39: ""You have heard that it was said, 'An eye for an eye and a tooth for a tooth.' But I say to you, offer no resistance to one who is evil. When someone strikes you on (your) right cheek, turn the other one to him as well." NAB.

Jesus made other changes to the accepted understanding of what God had commanded. The dietary laws required a Jew to abstain from certain foods or become unclean, i.e.. out of harmony with God. See Lividicus 11. But Jesus declared food clean.

Mark 7:14-19. "He summoned the crowd again and said to them, "Hear me, all of you, and understand. Nothing that enters one from outside can defile that person; but the things that come out from within are what defile." When he got home away from the crowd his disciples questioned him about the parable. He said to them, "Are even you likewise without understanding? Do you not realize that everything that goes into a person from outside cannot defile, since it enters not the heart but the stomach and passes out into the latrine?" (Thus he declared all foods clean.)" NAB.

In Mark 7:1-8 Jesus disallows the ceremonial washing the Pharisees taught was required. He did this despite Lev. 10:10 "You must be able to distinguish between what is sacred and what is profane, between what is clean and what is unclean..." NAB.

Because each of Jesus' statements are without error, their true meaning must be non-contradictory, that is each apparent change in the Law of God must not contradict his statement that the law cannot change. Thus the Catechism of the Catholic Church says in section 1967 "The Law of the Gospel "fulfills," refines, surpasses, and leads the Old Law to its perfection..."

Jesus himself accuses the Pharisees of changing or even negating God's genuine law. Mark 7:13: "You nullify the word of God in favor of your tradition that you have handed on." NAB. Therefore, what the religious leaders were teaching did not conform to what God's law actually was. How could he know this, or make this assertion? By being God's Prophet, Messiah, Son, and being God Himself, the second person of the Trinity.

St. Paul teaches: 1 Corinthians 9:20-21 "To the Jews I became like a Jew to win over Jews; to those under the law I became like one under the law--though I myself am not under the law--to win over those under the law. To those outside the law I became like one outside the law--though I am not outside God's law but within the law of Christ--to win over those outside the law." NAB.

Romans 13:8-10: "Owe nothing to anyone, except to love one another; for the one who loves another has fulfilled the law. The commandments, "You shall not commit adultery; you shall not kill; you shall not steal; you shall not covet," and whatever other commandment there may be, are summed up in this saying, (namely) "You shall love your neighbor as yourself." Love does no evil to the neighbor; hence, love is the fulfillment of the law." NAB.

 

We are bound to the old Jewish Law of Moses only to the extent it has been confirmed, ratified, and restated by Christ.