There is a common question put to atheists: Why don't you believe in God? The tone can range from curiosity to bafflement to aggression. I tend to get it especially because of my background. My father is an Episcopalian priest, my mother is a deacon, and all four grandparents were Elders in the Presbyterian Church. I come from a very strong Christian background. And yet, I have not rejected my parents. I didn't reject Christianity because it was shoved down my throat, as some of my friends did. In fact, I still adamantly defend Christianity, because I deeply admire the way that my family has always lived in their faith.
So why then am I not a Christian?
The answer is fairly complex and involves a number of factors. I think that any decision of this magnitude should be complex. If I ask you why you're a Christian, and your only response is "That's just the way I was brought up," I'm not likely to have much respect for you. Your faith should be put to the test of rigorous critical thinking, just like any other decision. And you should examine the other options available to you, just like any other decision. The simple fact that so very few people do this is very disheartening to me.
I can boil down my reasons to four fairly simple ones. Two are logical, and two are emotional.
First, I simply don't think that a divine being is logically consistent. This is most especially true of the Christian God, who is the most extreme example of divinity to ever exist. There are a number of logical issues that are well documented in the literature. The Problem of Evil (i.e., if there are powerful beings who love us and watch out for us, why do bad things still happen to us?) is the hardest to overcome. But for me, the primary issue is this: If there is _a_ divine being, why would humanity ever worship any other divine being? If God exists, why did cultures ever arise that could even conceive of false idols? If there is a pantheon of gods, why did they allow Christianity to shut them out? Even allowing for free will, it wouldn't take much for a divine being to simply manifest to every culture on the planet. If the humans get it wrong the first time you manifest, just manifest again a couple generations later and set them back on the right path. The simple fact that this doesn't happen is strong evidence to me that there is no divine being.
Second, I don't think that the Abrahamic God (the God of Christians, Jews, Muslims, and a few other sects) in particular can exist, precisely because of the state of His Church. The Church does not act in accordance with His teachings. I could accept that society as a whole must be allowed to stray from the path in order to allow for free will. But His priests should not. The constant failings of His servants on both a personal and an institutional level is simply appalling. It only makes sense if their God is a construct of Man.
Third, we shift gears to the purely emotional. I have control issues. The simple concept of vast inhuman beings pulling the strings of my destiny twists my gut and sets my teeth on edge. I choose to believe that there are no gods, because gods frighten me. On a similar note, I find the exhortation, "Turn your life over to God, and accept His plan" (similar ideas exist in most religions) to be horrific. You are human. You have the gift of free will. It is what sets you apart from the animals. To simply abandon that in servitude to a higher power is something I can't even understand.
Fourth and finally, we get to the reason I lost my faith in the first place. I have never heard the voice of God. When I was a child, I went to Sunday school faithfully. When I was a teen, I studied the catechism and prepared for my Confirmation. I studied and learned. I also prayed. Never once did I hear an answer. And I'm not talking about some miraculous event proving God's existence. I know that he is more likely to speak in the still, small voice. I was open to that. I never heard it. It makes it hard to believe that someone up there loves me, when they refuse to acknowledge me. After losing my faith, I looked to other religions, particularly pagan ones. Again, I never heard a calling. If there are any gods up there, they clearly don't want me. So, in a nutshell, screw them.