Revelation 20 specifically records two separate resurrections. First it references a group of individuals who will reign with Jesus Christ for 1,000 years—a time period commonly called the "Millennium"—and then it references "the rest of the dead," who will be resurrected to life after the Millennium years are over (Revelation 20:4-5).
Describing the events after the Millennium, the judgment of the rest of the dead is addressed and the eventual end of those who refuse to live by God’s way is outlined—a second death in the lake of fire (Revelation 20:12-15).
God’s magnificent plan takes into account individuals who did not know God, or who didn’t fully understand Him in this life.
We can read these passages and sometimes be concerned for our friends who don’t share our beliefs, or people we know who might be atheist, agnostic or of a different faith than our own.
It’s important to remember that God is a merciful God, and he will not forget the promises that he has made (Deuteronomy 4:31). He also desires that no man should perish, but all should come to repentance (2 Peter 3:9). The passages in Revelation 20:12-15 are describing all of those individuals who have ever lived being brought back to life in a general resurrection and being given an opportunity to truly know God and His ways, some for the very first time.
They will have their opportunity, just as you have; and they will have a choice to make, just as you did.
Death itself is referenced in numerous places in scripture as sleep (Daniel 12:2 for example), and that’s not a coincidence. When a person dies and their eyes close for that final time in this life, Scripture states they know nothing in the grave while they await their time to be resurrected (Ecclesiastes 9:5; Acts 2:29-34). After the 1,000 years are ended, when God restores their physical bodies (Ezekiel 37) and resurrects them back to life, their eyes will open once again. Like a child that falls asleep in the back of the car and awakes in someone else’s home, this resurrection might be disorienting or confusing as they process the last memories they experienced before their death and their newfound reality.
It will be helpful to have someone there with a familiar face. It will be helpful to have a person who lived this way of life here on earth and has experience with it, someone who can help to teach them the way of God so that they can have their opportunity to make their choice.
But the choice is theirs.
After they have been raised and shown God’s way, if they choose not to live by it, they will be sentenced to the lake of fire, where they will cease to exist (Revelation 20:14-15).
God’s magnificent plan takes into account individuals who did not know God, or who didn’t fully understand Him in this life. He is a merciful and loving God and greatly desires to bring many sons to glory.