Will literal Heaven and Earth cease to exist? Many of us were raised believing this because it literally says this in the bible and Jesus was the one who said it. First in Matthew 24:35,"Heaven and Earth will pass away, but My words shall not pass away", and also Matthew 5:18,"Till Heaven and Earth pass, not one jot or tittle shall in no wise pass from the law; till all be fulfilled". The problem is that we are reading a 1st century book with 21st century lenses most of the time, and we do not understand apocalyptic language which is full of hyperbole and metaphors and rarely literal. We also must put ourselves into the minds of 1st century 2nd temple Jews who were the audience that Jesus was talking to.
The question should be why would Heaven ever need to pass away since that is a perfect place of God's manifest presence? Plus we are told several times in the old testament like Psalm 104:5 & Ecclesiastes 1:4 that the Earth remains forever. We should also ask if Heaven and Earth didn't pass away then are we still under the law and should we throw out most of the epistles which tell us we are not? Lastly what is," till all fulfilled", talking about? The end of the World? The fulfillment of all bible prophecy? The law fulfilled? We know that Christ in His finished work fulfilled the law and the prophets, right?
To understand what Jesus meant we must realize that to a first century Jew Heaven and Earth was the temple and the whole Judaic system of temple sacrifices in Jerusalem. There are many old testament verses that call the people of Israel and the Temple and its system Heaven and Earth, Isa 51:15-16, Hag 2:21-22, Deut 32:1 to name a few. Josephus a Jewish historian hired by the Romans to take meticulous records of the war from 67-70 A.D. says in his writings in " Antiquities of the Jews", book 3, chapter 7," when Moses distinguished the tabernacle into 3 parts, and allowed 2 of them for the priests, as a place accessible and common, he denoted the land and seas, these being of general access to all; but he set apart the third division for God, because Heaven is inaccessible to men".
2nd temple Jews called the outer court the sea, then the inner court the Earth, and the holy of holies the Heavens where God dwells. So to a 1st century Jew, who was Jesus' audience by the way and not 21st century Americans lol, when their temple and holy city was destroyed in 70 A.D. THEIR Heaven and THEIR Earth did pass away. This fulfilled the law and the prophets for there was now no place to offer sacrifices, and the law which the cross had made obsolete had now passed away (Heb 8:13).
We are then told in Revelation 21:1,"The first Heaven and first Earth were passed away, and there was no more sea". To understand that we must ask what was the "first" Heaven and "first" Earth to 1st century Jews? Their temple (Heaven and Earth) had been completely destroyed and now there is a new Heaven and new Earth which is the Temple not made with hands of bricks and straw and mortar but made by God. No wonder Paul has to say it twice when he says,"know ye not, know ye not, YOU are THE TEMPLE". Also, there is no more sea or outer court with the brazen altar and laver of washing where the priests would have to continuously offer sacrifices and wash themselves, because now we are cleansed "Once for all" by the blood of Jesus.
We are now in a new covenant, with a new Adam (Jesus), a new Eve (the bride, the lambs wife), living in a a new Jerusalem and city (church of the firstborn), a new temple (body of Christ), enjoying the fruit of the 2nd tree (life), with the first tree (law of sin & death) now cut down and defeated, and the Lambs resurrection life infusing us to enjoy the life of the age to come (eternal life, aionos zoe), Heaven invading Earth.
So just know that literal Heaven and Earth are NOT going anywhere and the law has been completely fulfilled and the only temple God desires to live in is the tabernacle=naos, inner sanctuary, holy of holies - among men, which is our bodies. So my friends do not be afraid of the World coming to an end, but instead realize that you and I are now the tabernacle and anyone in Christ is a new Heaven and a new Earth/new creation and He desires to be at rest in us.