I was once VERY religious. Christian too. I no longer am, and I now consider myself mostly atheist. This is for various reasons.
- Too many contradictions in all religions and their texts.
- Science is currently explaining most of what religion says to be "Well, we don't know the answers, so God is the only possible answer!". Sorry, but just because we don't know certain answers doesn't cut it for me that there must be a God. Science is explaining everything not just right down to the big bang, but also to HOW the big bang started -- without needing any divine intervention.
- There are thousands of different religions, all of which claim to be the truth.
- No one has even attempted to define just what exactly God is, how such an intelligence can exist eternally, control everything, and know everything. We know nothing about God when it comes down to what "his" attributes and properties are. It's a total cop-out.
- A big reason for me is that religion is full of way, way too much hate. In fact, Judaism, Christianity, and Islam all make it clear that God sometimes considers slavery, rape, terrorism, genital mutilation, and even child rape and murder to be holy sanctioned acts. I don't believe in the whole OT to NT conversion either. It doesn't seem logical to me that an all-knowing God would decide he was wrong and do a complete, utter back-flip on morality. I question anyone who believes in such a God, especially if they believe in a God who once ordered such atrocities.
- Teaching children that there is a hell they could burn in is terribly cruel. Even teaching them about heaven when it may or may not exist is cruel to an extent.
- There are multiple scientific proofs debunking the spiritual, and metaphysical. And yes, there are even multiple proofs, which believe it or not, debunk the existence of God.
There are good evidences that the divine encounters in the past, such as Angels, Demons, etc, were all misinterpreted for what we today would call encounters with extraterrestrials -- which are much more likely to exist than spirits floating around in the clouds, bringing us in need of witch doctors. I don't consider myself as much of an atheist as I recently did, because I'm seeing again that religion may have some relevance in this regard. How so? We just don't know, and I'm not about to assume just because we don't. I'm even believing yet again that there may be an afterlife (which btw wouldn't mean there's a supreme creator), though that may be wishful thinking. An afterlife would likely have something to do with extraterrestrial technology itself.
However, before I believe in extraterrestrial intervention with any certainty, I believe with more certainty in my atheism, that there is no God, and that all of existence can be explained scientifically. If I'm wrong about any of this, that needs to be proven. The burden of proof is on the one making the accusation. All religious theists claim to have 'proofs' for their different religions, usually all such proofs being equally stupid and refutable. My biggest reason for being an atheist: There is no proof that God exists and there is no proof that any one religion is right. If there is a God yet no true religion then we can't possibly know what God wants from us, since there is no true scripture or dictation. So we might as well live like atheists. Believing in God just to save ourselves would be a futile assumption.
And the concept of there being a God AND a true religion is a scary thought, since the gods of all those religions are pretty fucked up.