The question is most likely referring to the following scriptures:
Matthew 24:35, Mark13:31, Luke21:33, “Heaven and earth shall pass away, but my words shall not pass away.”
2 Peter 3:10, “But the day of the Lord will come as a thief in the night; in the which the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up.” If these scriptures were literal, the question’s point would be valid.
These texts are in reference to the “passing away” or destruction of the symbolic heavens and symbolic earth. The “earth” represents the evil earthly governments and social orders. Whereas the heavens are the false church systems. In Isaiah 24:19-23, the earth in verse 19 is obviously symbolic because in verse 23, the Lord is reigning from Mt. Zion and in Jerusalem.
Isaiah 24:19-23: “The earth is utterly broken down, the earth is clean dissolved, the earth is moved exceedingly. The earth shall reel to and fro like a drunkard, and shall be removed like a cottage; and the transgression thereof shall be heavy upon it; and it shall fall, and not rise again.
And it shall come to pass in that day, that the LORD shall punish the host of the high ones that are on high, and the kings of the earth upon the earth…Then the moon shall be confounded, and the sun ashamed, when the LORD of hosts shall reign in mount Zion, and in Jerusalem, and before his ancients gloriously.”
The returning Lord will judge and find the present nations, religions, and their works to be unrighteous. These ecclesiastical and social orders on earth and in the spiritual heavens will be removed and eliminated. Then Christ will establish His righteous rule on earth and the Lord’s prayer will be fulfilled: “…thy kingdom come, thy will be done on earth as it is in heaven.” We are assured that the planet earth will not be literally destroyed because “…the earth abideth forever.”