Isaiah 65:
17 For, behold, I create new heavens and a new earth: and the former shall not be remembered, nor come into mind.
18 But be ye glad and rejoice for ever in that which I create: for, behold, I create Jerusalem a rejoicing, and her people a joy.
19 And I will rejoice in Jerusalem, and joy in my people: and the voice of weeping shall be no more heard in her, nor the voice of crying.
20 There shall be no more thence an infant of days, nor an old man that hath not filled his days: for the child shall die an hundred years old; but the sinner being an hundred years old shall be accursed.
21 And they shall build houses, and inhabit them; and they shall plant vineyards, and eat the fruit of them.
22 They shall not build, and another inhabit; they shall not plant, and another eat: for as the days of a tree are the days of my people, and mine elect shall long enjoy the work of their hands.
23 They shall not labour in vain, nor bring forth for trouble; for they are the seed of the blessed of the Lord, and their offspring with them.
24 And it shall come to pass, that before they call, I w ill answer; and while they are yet speaking, I will hear.
25 The wolf and the lamb shall feed together, and the lion shall eat straw like the bullock: and dust shall be the serpent's meat. They shall not hurt nor destroy in all my holy mountain, saith the Lord.
Great promises of God
Unless you believe in some bizarre and strange assemblage of resurrected believers and non-resurrected sinners, this particular portion of scripture is talking about the positive outcome of spreading and acceptance of the gospel of Jesus Christ comprehensively - before He returns.
Some get thrown by verse 17, where it says this: "For, behold, I create new heavens and a new earth: and the former shall not be remembered, nor come into mind."
Many equate this with the period of time when we're resurrected and living in our new bodies forever. It's obviously not what it's talking about here. Jesus initiated the creation of the new heavens and new earth when He was incarnated. He was the Lord from heaven, we're told in the Bible. He came down out of heaven as the foundation stone of this new Jerusalem, and the gathering in of the first believers around Him, as evidenced by the 12 apostles being mentioned in Revelation 21:14.
"And the wall of the city had twelve foundations, and in them the names of the twelve apostles of the Lamb."
They were the foundation of the wall of the city, and they were living human beings formed and shaped by the words of Jesus. This is one of the reasons we're taught to set our minds on things above and not things of the earth. It's not that we're to think of mystical, strange things we believe are residing in heaven, but are to rather embrace the higher things represented in the person of Jesus Christ, which He spoke of and displayed in His person, and throughout the entirety of the scriptures.
The culmination of all of this is revealed primarily in verses 20-23. It promises a world where babies won't die prematurely, where old men will live a long life, where the fruit of our labor will enjoyed while we're alive on earth, where we won't have what we build or plant taken away from us.
Some of the struggles we now have will be gradually removed as the effects of the curse are reversed in conjunction with obedience to the word of God. This will take time to work out, but this span of time and all it represents will happen before the return of Jesus Christ to resurrect all of us.
There really will be a golden age on the earth. These verses in the Bible give us a glimpse into what it will be like when God's people walk in obedience to all His commands.
Everything the vast majority of people want are promised to be fulfilled by the Lord. Our job while we're on planet earth is to do our part by walking in obedience to the light we now have, advancing and hastening the day when God will be glorified on the earth by a people that reflect His true nature.
This is also confirmed and reinforced by 2 Corinthians 5:17. It says this:
Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new.
The word creature there is more accurately "new creation." Also notice old things are passed away, behold, all things are become new. Paul was saying that the promises in Isaiah 65 were already in motion. That was almost 2,000 years ago. God continues to work toward that end in His people.