We don't know when the world will end, it could be a really long time. But when it does, it will be an absolutely horrible time on earth, worse than ever before. Putting an end to it will be a relief. Those who honor God will escape or wind up in heaven. Only the wicked need to worry about long term suffering. God promises to be a fair judge, and He is love, so we trust that only those who truly deserve it will find severe punishment.
On why we spread the word of God in general...
It's not just a major commandment, it's a big part of why we're here. God offers us everything: Eternal life, blessings and a relationship with Him in this life, and endless wisdom and fulfillment. In exchange, we are to live for Him. We are to serve others, feed the hungry, heal the sick, and ease the world's suffering. But to help someone find God and all his gifts and gain access to eternal splendor with Him... is the biggest deal of all.
It's actually been written that we are responsible for making sure everyone we know who does not know and understand God, hears about Him through us.
And that's as it should be. He is a God of love. He wants as many of His children as possible to live with Him in Heaven for eternity. He knows we all need some help and good examples to bridge the gaps of unbelief and partial belief. He asks US to do His legwork and heal the world, as well as bring as many people into heaven as we can.
With every good thing we do for Him, we gain reward. Blessing in this life, and in Heaven as well. He says even if we give a cup of water to a child, we will be rewarded. He says whatever we do for the least of people, it's as if we did it for Jesus Himself. He says to not worry about storing up riches in this life as riches can be stolen or destroyed, but to store up treasures in heaven. This is to be our life plan.
To live for love and healing and making a huge difference in this world, with all God's help at our disposal, experiencing His supernatural power in the process.... only to be rewarded with eternal life and living by His side?
I haven't heard of a better plan anywhere.
This is our God. This is our Jesus. This is truth. If we check it out thoroughly and do not give up, we will all find this truth. It checks out if we are truly unbiased toward it. And it's available to all of us.
From this side of the fence, atheism is hard to understand. No heaven. No guidance or wisdom or protection from God. No comfort in times of pain, and as we get close to death. The freedom to do whatever we want invariably results in disappointment, and often extremely bad circumstances. God is the major reason people stay honest and helpful in selfish and corrupt world, often enduring pain and humiliation for it. If everyone rejected God, when things get tough, there's little reason not to steal, hurt, force, and destroy. Morals lose their meaning and we become like animals. There's places in the world like that already, and they never have our God at their center. Countries that do have peace.
Away from God's path, we run on the pleasure of youth, gaining prosperity, and things. It all fades away and leaves us empty. At the end of our lives, it's love, family, and honor that has sustained us and given us true meaning. It keeps our spirits warm and strong even when the body is broken and feeble. These are the things God talks about so much. Love. Honor. Spirit. To focus on these things and stay off the paths of selfish accomplishments and pride, as is our nature without God's spirit interceding in some way or another.
On God's side of the fence, we see Him in everything. Every bit of nature's design. Babies and childhood. No two snowflakes alike. Our voices, faces, fingerprints also unique. DNA and brain structure so incredibly complicated a designer of deity is required. Love itself. Life itself. Every good and beautiful thing that happens to us. Without a God at the center of it all, all this happened as random chance. All things fell together with no oversight.
But with God, it all becomes a long series of amazing gifts designed just for us. He wanted a strawberry to taste that way to us. Cows eat grass all their lives. We get a full buffet of not just food, but everything that exists.
He mixes it all in with some hard times and rain and ugliness. He wants to see what we focus on the most. All the beauty and wonder and light and love, or all the things that make us want or need to reject Him.