If you will go to the Old Testament and follow every line of it through to the New Testament, you will see the changes very clearly. There wasn't one change made by Christ in spirit and truth, in the spiritual context of God principles. Atonement was made by blood. Forgiveness through the blood of Christ. The High Priest told them the will of God through the Urim and Thummim, Christ lets us know God's will, He is our High Priest. For instance. We are to understand exactly how Christ is related to all and how Christ changed all---not by adding anything or taking anything away.No I am not confused about that debate. But you have to separate the tradition and law do to the changes that were made between the old testament ( old covenant ) and the new testament ( new covenant ). This is an area some Christians don't like to accept, that there was changes made. And from our Lord Jesus to the writings from Paul, Peter, James, and John you can read those changes.
Although we are told by Paul that it is a principle of God that we can designate another day as the Sabbath, we are to choose a day for the Sabbath. Christ did not change that principle.