Unless I have misunderstood your post, please!
Ok then.....
Maybe you did not realize that you created a mixed message in your post. Your words suggest one thing and the scripture you presented speaks to something quite different. So what is the true message you are sending?
I will assume that your post says that Law of Moses and the use of the Prophets under the Old Covenant are still in force today. And they operate the same way...and that is completely untrue.
Now the actual Law(s) of Moses does not change although the way we approach and use it today is very different as a believer. God still uses the Law he first laid out to Moses as his perfect standard to reveal how evil and abominable we are in his sight. Unbelievers are really under its first and primitive form today, not believers.
When I say that Law has been replaced or has become or made obsolete I speak to a careful and thoughtful inquiry into its new use and the interpretation of it. Christ has completed and replaced its primitive state, thank God indeed.
Under grace and Christ we have the Law of Christ that includes the Law of Moses as it foundation and much more residing within our heart by the Spirit of God, and not on any stone or written on paper for a scribe or lawyer to interpret anymore for us. The world actually lives and thrives, based on it legal written interpretation. Under the Law of Christ (with the Law of Moses included) it clarifies and adds real meaning to the Law where it did not before Christ. In fact the Law was being abused by the religious authorities. The use of the Law for their purposes had to stop. They were leading people into confusion and they could never find peace and the Kingdom of God.
Now into Luke 16...I would suggest you go back a few verses to capture the local context.
Luke 16:13-18 speaks to the Pharisees and Scribes, who loved material things and money and loved to legislate things of the Law to justify their legal and prideful positions. Yahshua's Father knew their hearts of course as Yahshua said. They believed that wealth was a sign that a man was a good man in the eyes of God. They regarded material gain as a reward of that goodness; not knowing that the more they exalted themselves before men, the more they became an abomination to God. And so in their defense, they raised their noses up to Yahshua and called him the self-righteous one, someone who wanted a face of public acceptance with the people, and not them.
Jesus/Yahshua stuck back at them and said they value (in the hearts) things that were detestable to his Father. They did not have the Spirit of the Law within their hearts, as intended.
Now before John the Baptist, Christ, his disciples and the gospel there was the primitive form of the Law and it usage along with the many Prophets under the OC. And now under grace many were entering into the Kingdom, tax collectors and sinners alike, and many under duress, under hostile conditions from other men and evil forces. They wanted the 'new' Law in effect. Not the Law interpreted by the Pharisees and the wealthy and powerful.
He is saying in essence that whereas the law was before imperfect, it is now being perfected. So with regard to the prior understanding of material wealth, now been perfected in the teaching of non-possession or of non-material value. This is why the following verse is connected:
'Whosoever putteth away his wife, and marrieth another, committeth adultery: and whosoever marrieth her that is divorced from her husband committeth adultery.'
The point stressed by Yahshua is that the Law as its original form will stay and not itself be altered, it is of his Father of course. Christ came to complete it and then also rescind it, not its words; to PERFECT it, place it in our hearts and with a quite different view and understanding of it that no man could ever again legislate or condemn someone for breaking the Law or even if abiding by it.
So Jesus emphasized that the establishment of the Kingdom was not the end of the law, as I also have stated, evidentially not that clearly up to now for some.
In general, rescinding something or replacing something does not say the original article has been destroyed or ended at all. Many times and very often those of ignorance, the knee-jerky folks accuse others of their own contrived shallow thinking onto others and into even the public arena, - of a quite different meaning and intent as the source for this ill-conceived accusation.
So Christ being the perfecter of the Law might make you happier I think.
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