This is cosmological symbolic language which describes the passing away of the Old Heavens and Earth, epitomized on earth in the visible removal of the obsolete Old Covenant system, temple and people by the destruction of Jerusalem and the temple. There is a major consummative change from the Old Covenant to the New Covenant that is taking place. The already obsolete Old Heaven and Earth animal sacrifice cosmological world order, epitomized in the ceremonial system of the temple, the sacrifices, the temple priests, circumcision, etc. are all now forever removed. Jesus had fulfilled the law. He was the promised Messiah. The Jewish leaders refused to recognize Him and continued on with the old obsolete ceremonies and Laws. Their trust was in their own works and not faith in Jesus –> they too are now judged and destroyed. The New Heavens and Earth cosmological world order through the blood of Christ is fully consummated. The conquered spiritual realm has been fully gathered and consolidated under the throne of Christ (read Rev. 11:15), and His New Heaven and Earth Kingdom is fully consummated reuniting “heaven (unseen realm) and earth” (seen realm) through the finished redemptive work of Christ (read Eph. 1:10).
[For a more in-depth study see eschatology “Study Series 7 Lesson 4 Matt. 24:29-31”]