Heaven and earth shall pass away: but my words shall not pass away.
The universe and the earth will be surpassed but my words will not be surpassed.
Christ defines the universe and our world as the will of God coming into existence. I have written elsewhere that Christ's use of the term "heaven" does not conform at all to our modern idea of a Christian heaven. Rather it is a way of expressing the idea of existence outside the boundaries of our world. Both our world and the rest of what exists in an expression of God's will.
The line from the Lord's prayer translated as "Your will be done on earth as it is in heaven." is written from our modern Christian idea of "heaven." The Greek translated as "Your will is coming into existence as in the heaven and earth.' Heaven and earth are understood to encompass all of creation, which is why I prefer to translated as "the universe and our world."
As the universe and our world continue to change, the fullness of God's design is unfolded over time. this is understood to be the tangible result of God's will acting in the material world.
Here, Christ is saying that both the universe and our world continue to surpass themselves. It is their nature. The will of God is expressed over time. For God, the moment of creation is all time. When he pronounced the creation good, he was taking about its completeness over time. His perspective is not our perspective because we can only witness a small slice of that creation taking place during our lifetimes.
Here, however, Christ says that there is a different between the development of reality over time and the nature of his words. His words are timeless. They are not surpassed or improved upon over time. What changes over time is our perspective and understanding of his words.
The statement can be taken to mean that the abstract as expressed in words surpasses the concrete as expressed in the world and the universe.
οὐ μὴ "Not" is from mê (me), which is the negative used in prohibitions and expressions of doubt meaning "not" and "no." It is modified by the preceding word: οὐ (ou) negates fact and statement; μή rejects, οὐ denies; μή is relative, οὐ absolute; μή subjective, οὐ objective.
παρελεύσονται "Shall...pass" is from parerchomai (parerchomai), which means "go by", "pass by", "outstrip" (in speed), "pass away," "outwit", "past events" (in time), "disregard," and "pass without heeding."