Original sin

Original sin is the Christian belief that, because of Adam and Eve's sin in the Garden of Eden, all humans are born with the weight of that sin on their backs. If a person doesn't accept Christianity within their lifetime then this sin will send them to hell.

Problems with original sin
Religious skeptics question the justice in the God character's decision to punish every human that will ever exist for the sins of a pair of people who lived thousands of years ago. In law, the only people that bear the weight of a crime are the ones that perform it. For example, if a father assassinated a political leader it wouldn't be just to punish his great-grandson for the crime as well.

A larger problem arises with the set-up of the Garden itself. God created Adam and Eve without knowledge of the difference between good and evil. He then told them that they could eat anything in the garden except the fruit of the so-called Tree of the Knowledge of Good and Evil. He also gave humans free will because he wanted them to be able to freely choose him. Thus, when they ate from the tree he was able to punish them for disobeying him. However, the problem arises from the fact that Adam and Eve, being created without the knowledge of good and evil, would not have known that it was wrong to eat from the tree until after they ate from it. They basically had the moral intelligence of infants.

Furthermore, if God is omniscient then he must have known before he even created them that they would disobey him. If he knew beforehand, then why would he create the tree in the first place? Furthermore, some argue that if God knew beforehand that they would disobey him, then they had no real choice in the matter. They had to disobey him because, if they didn't, God would cease to be all-knowing. In essence, the entire Garden of Eden was a trap.