It is our worst fear and our ultimate fate: Death. The one truth that we can all be certain of is that one day we will die. Atheist or theist, republican or democrat, Gutmensch or murderer, none of them will escape death.
Death can be accepted in two ways. One either believes that death is the end, or one believes that death is the portal to a new and eternal life. Almost all religions on this planet have faith in an afterlife. A place where one experiences constant joy and happiness. To get in, you only need to pass one test: You need to have faith in God.
I will argue that the very idea of an afterlife makes concepts like 'morality’, 'good' and 'evil' fall apart. As an example I will use the Christian afterlife, but feel free to replace 'Christian' with 'Islamic', 'Mormon' or whatever you like.
Heaven: Not What You'd Expect
To enter the Christian afterlife God only asks one thing of you. He wants you to turn to him and ask forgiveness for your sins. Now let's imagine this is true. Hitler was a Christian, so by Christian morality Hitler is in heaven. But that's not all. By these standards murderers, child rapists, thieves and even genocidal psychopaths can enter the heavens just by turning to God on their deathbeds. To hold this view is not in any sense moral by modern standards.
Believing in an ultimate judgment after death does not make us moral if that judgment can be turned around by a mere thought. In fact, it means the opposite. Why act moral in this life if all your wrongdoings can be forgiven by just asking for forgiveness? Believing in an afterlife doesn't make us moral, it makes us immoral, selfish and irresponsible creatures.
Judgement of Criminals
Imagine Adolf Hitler standing before the ultimate judge. According to Christian scripture something similar to the following would happen:
God: "Adolf, you have murdered millions of innocents, started a world war that killed millions more. You have treated people like garbage, started a genocide and committed the crime of ethnic cleansing (something the Catholic church shouldn't be all too unfamiliar with). But since you are a Christian and asked for forgiveness, you may enter heaven."
Is this how we should judge people? After centuries of perfecting a justice system, this is how we judge? The very idea of this 'heaven' is immoral. It is immoral towards those who suffer and have suffered in all of human history. It should not comfort us to know that a lot of criminals are in heaven. It should scare us, a lot.
Where there is a crime, there is a victim. Any rational person would know that if a criminal were to seek forgiveness, he has to get it from his victims. Not in Christian morality though. In the Christian morality a criminal can somehow be forgiven without facing his victims, because God can forgive them. Ask yourself, in what sense is this moral?
If I shoot your kid, I'd have to seek forgiveness from you. Not if I'm a Christian though. If I were to be a Christian I could just ask God for forgiveness and go to heaven anyway, even though I shot an innocent child. But Bill Gates, a man who donates millions of dollars to charity will go to hell because he didn't have faith in God. It is beyond absurd to believe that this contributes to society in a positive way.
Truly believing in an afterlife basically devalues the life we are in now. What are ±75 years on Earth worth compared to an eternity in heaven? Barely anything if you ask me. It is downright greedy to not be satisfied with one life and demand a second one. In many people this greed is so strong that they simply start to image there must be an afterlife. It is this imagination, this fantasy that takes away the value of the life we have. And by devaluing your own life, you automatically devalue the life of any other being on this planet. We should not even be thinking about an afterlife. Instead we should be doing anything to make this life worthwhile.
Stop worrying and start living. It's the only chance you have.