Atheists don't believe in God because their way of knowing if something is real is to have proof. There's nothing wrong with that, but the whole point of faith is to know God is real even if there isn't any hard evidence.
This is why I don't believe in God, but also why I am agnostic, I don't deny any gods existence either, because I have no hard proof of athiesim being true.
I Like to say that Jesus exists in the same way that Santa Claus exists--in the hearts and minds of the people who believe in him. And if that belief helps them to do good then it's a parable worth believing in.
I think the problem most atheists have is when theists try to punish them into believing.
I'm perfectly willing to believe in the existence of a historical Jesus. However, he was a nice Jewish boy and probably wouldn't make many of his present-day worshippers happy.
Prove it.
There is a reason The Clergy Project exists and why thousands of preachers know the truth (there is no god/gods and the whole thing is made up) yet go on with the charade just to keep a paycheck rolling in.
But do your own research...as long as it's legitimate research and not a cognitive bias, "let-me-check-with-a-pastor-who-will-tell-me-what-I-want-to-hear" research project. That's not research.....
Read Richard Carrier's On the Historicity of Jesus
Read Daniel Dennet's Caught in the Pulpit
Read Sam Harris' The End of Faith
Read Aron Ra's Foundational Falsehoods of Creationism
Read Richard Carrier's Not the Impossibly Faith
Read Richard Dawkins' Outgrowing God
Read The Skeptic's Annotated Bible
And read up on BIBVIZ.ORG
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