After Jesus died on the Cross He spent three days in Hades below the earth. He when down there to let Satan, the demons, and the fallen Watcher Angels know they had failed in stopping Him from coming to Earth as the Messiah. Genesis 6 tells what the 200 Watcher Angels did to try and stop Him.
Across from horrible Hades was beautiful Paradise. The believing Old Testament Saints and the believing Gentiles went to Paradise after they died. Father Abraham had already been in Paradise for 3,000 yrs. when the poor beggar man died and came there. When the rich man died and went to Hades he asked Jesus if the beggar over the chasm in Paradise could bring him a drop of water for his thirst. Jesus said no because it was too late.
The one thief on the cross said he and the other thief deserved to die but Jesus had done nothing wrong. Jesus told the one thief he would be with Him that day in Paradise.
When it was time to leave, Jesus gathered every person in Paradise, including Adam and Eve, and took them to Heaven. Some of the people of Paradise who had died recently got to walk through the city of Jerusalem to let people know there was life after death. After saying goodbye to their family and friends, the Angels took these people to Heaven.
Paradise is now empty but Hades is still full of unrepentant sinners until judgment day. Hades is pitch black with small holding tanks for each unbeliever deep beneath the earth. You can’t see or talk to other doomed human beings; only demons are allowed in to torment.
Nobody is in the fiery Hell, yet, but some people have seen Hell. The first people thrown into the fiery Hell at the end of the Tribulation will be the Antichrist and the False Prophet. All the nations of the Earth will be judged by GOD according to how they treated and mistreated Israel. Satan, the demons and his fallen angels will all be thrown into the dark, bottomless pit for 1,000 years while there’s a Millennium Time of 1,000 years of Peace on the Earth.
During the peaceful Millennium the lamb will lie down with the lion and the people who survived the Tribulation will rebuild the torn up cities after war and prosper greatly. Prisons will be practically empty, while schools will teach real history, no common core and inspiring new things to the students. The politicians will not be as greedy but more helpful. With less government people will be able to make better decisions, be more generous and helpful to all mankind, the Earth and the animals. People will work less hours and have money for longer vacations.
People will trek to Jerusalem to see and worship the Trinity (God, Jesus, & Holy Spirit) where Christ will rule and reign over the new Earth. It will be a time of great peace, cooperation in cleaning up the Earth and rebuilding the torn cites of war. Rebellion will not exist because the contented inhabitants are treated fairly and able to do the things (passions) they love. There will be witty inventions, unusual talents, new land discoveries, healthier food, water and air, outer space travels, ability to prosper, less crime & fewer prisons, fewer hospitals due to finding cures for diseases.
By the end of the 1,000 years there will be millions of people living and prospering peacefully on Earth. Man will still give in to the temptation to sin but any serious sinful activity will be nipped in the bud the right way. People will still need & yearn for a relationship with Jesus Christ. Most of the people will love and accept Him as their personal Savior but some people will think they are good enough without a savior.
All through the peaceful millennium, people will live much longer (800 to 900 yrs. old) like they did in the Old Testament. When an unbeliever dies they still go straight to Hades to wait for judgement. All the believers who die go straight to Heaven and have access to Earth anytime.
After 1000 yrs. when Satan and his evil minions are released from the pit they will use their old tricks to persuade unbelievers to rebel against Jesus. Satan and his fallen angels and demons will turn the unsaved against God by tempting them with signs and wonders to fool them into thinking they are as powerful as God. Satan will promise them power and wealth to follow him. Eventually, Satan will lead them to attack the throne of God that is on the earth in Jerusalem.
But, Satan fails to pull if off at the end because God zaps the army of unbelievers to smithereens the second their unholy feet touch the Holy Land. Michael and his army are awaiting in the clouds with the mighty Host to fight the fallen angels and demons, and capture Satan. Satan and the demons are judged by God and thrown into the fiery Hell for eternity; the unbelievers in Hades are judged by God and thrown into the fiery Hell; the fallen angels are judged by the saints and thrown into the fiery Hell with the antichrist and false prophet forever!
God will move His children from earth to Heaven for a while, so they can watch him from Heaven as He destroys the old, tired Earth and makes a brand new one, a hundred times bigger! (See Revelation 22) Believers will visit/live on the new Earth or travel to the new, massive universe of Nebula's, gigantic milky ways and worm holes to slide through.
They can visit in their eternal bodies or travel in galactic ships to claim a planet. Creative people can build unique amusement parks on planets for people to visit on birthdays, create a star war planet for laser-gun fun, hunt animals that talk, build medieval sets with fun dinosaurs, or have famous movies on planets, Children R Us Planet for the aborted children, etc. There’s no end to what can be created when God teaches us how to “think it” and wham, it’s there!! But, there will be no more marriage and no need to repopulate.