The opening chapters of the Bible tell us that when God created our first parents -- Adam and Eve -- they lived in a perfect world. And not only was the world perfect, but their relationship with God was perfect also.
But God warned them not to eat the fruit of one particular tree, because if they did, death would come upon the human race. In other words, God gave them a choice: to obey Him or disobey Him. Without that choice, they would have been like puppets, able to do only what God wanted. But God gave them a free will -- and one day they gave in to Satan's lies and chose to rebel against their Creator. As a result, the Bible says, "Sin entered the world through one man ... and in this way death came to all men" (Romans 5:12).
What would the world be like if they hadn't sinned? We can only speculate, of course, but I have no doubt that Satan would still be trying to get us to believe his lies and turn against God. But the reality is that Adam and Eve did give in -- and every day you and I give in also. That is why we need Christ, for only He can forgive us and bring us back to God.
But listen: Some day, we will live in a perfect world, if we know Christ! Some day, all sin will be destroyed and Satan will be bound forever! This present world will never be perfect -- but heaven is. Is your faith and hope in Christ?