I am likely to revisit this question repeatedly in this blog, at least to respond to various arguments for the existence of a diety.
For the time being, I wish only to give a short description of my top 15 reasons for not believing in the Christian god in particular. I have never believed in any other deity, not really. Some of my logic comes from Richard Carrier’s short book Why I Am Not a Christian. I have not bothered to give a thorough defense of any of these reasons, but this should give a hint of the type of thing I’m focused on.
My first reason for losing belief was that I learned evolution is true. I’m not going to list the evidence here because I don’t have space and am not a biologist, but one thing that helped me reach this conclusion is that humans have a chromosome pair that is two chromosome pairs stuck together. This chromosome was a prediction from evolutionary theory because apes have just two more chromosomes than humans. (See this video for a better understanding from an actual scientist.)
Obviously, evolution by itself doesn’t disprove any deity; there could be something supernatural starting/guiding the process. What it does show, unless you refuse to admit that animals can suffer, is that suffering existed for billions of years before any humans existed to commit the Original Sin that many Christian doctrines say is the cause of suffering. Besides, if the Garden of Eden is entirely metaphorical, why take the Crucifixion and Resurrection literally? There is much theological argument trying to work around that problem, but it is at least a crack in the wall – something Christianity cannot immediately explain away.
On that note, one of the historical problems of the Bible is that there is absolutely no evidence for any Adam or Garden of Eden. In fact, there is much evidence against it, most of it from the findings that support evolution.
Another historical problem with the Bible is that it is abundantly clear to any student of geography that there has never been a global flood. There cannot have been. There’s no evidence from the rocks. Besides, there isn’t enough water on the planet.
Further, not even Abraham is a historical character. He is a literary invention, as even Wikipedia shows.
Continuing the historical problems, Moses is another character from the Bible who never existed. There was no wandering through the desert for 40 years, and no plagues of Egypt, and no Commandments from Mount Sanai. I’m not a historian and this is meant to be brief, so I’m not presenting the evidence for these last few assertions, but these Biblical figures being fictional is almost as commonly accepted among historians as evolution is among biologists.
On a different hand, there are several moral problems with Christianity and/or the Bible. In particular, the Bible forbids neither slavery nor rape. Indeed, it allows the beating of slaves as long as they don’t die for at least a day or two (Exodus 21:20-21). In the case of rape, the woman can be put to death for adultery if she doesn’t scream loud enough (Deuteronomy 22:23-24) or be forced to marry her rapist (Deuteronomy 22:28-29). Clearly, these are NOT moral positions! (If you disagree, please seek help.)
Further, many sects of Christianity still forbid all forms of homosexuality, masturbation, and extramarital sex. While we should certainly not approve of cheating, there is no reason to forbid other consenting acts of sex. Masturbation has multiple health benefits, such as reduction of stress, and men are biologically programmed to ejaculate occasionally because they never stop producing sperm. Wet dreams happen for a reason, and that reason is purely biological. Homosexuality is a natural phenomenon observed in multiple species around the globe which, again, has a biological origin. To forbid it entirely is to forbid many people from ever experiencing the great pleasure of a romantic relationship. Extramarital sex, meaning sex without marriage or even sex outside of one’s own marriage with the consent of one’s spouse, has no legitimate reason to be forbidden. It can cause a great deal of pain, but with caution and without being forced to think sex is wrong, it can also bring a great deal of harmless and healthy pleasure.
Another moral problem with Christianity, or at least many sects of it, is that it forbids abortion and contraception. There is no moral argument for forbidding contraception. It does not end a life; it prevents one from beginning. To equate those two concepts is extremely irrational and logically leads to calling women murderers for menstruating or men murderers for masturbating.
Abortion, on the other hand, is less clear cut. It actually does entail the ending of a life, although not an independent one. However, if it is entirely illegal, it leads to women being thrown in jail for miscarriages. To me, this alone is enough to convince that abortion needs to be legal for at least the first trimester. Further, many of those who seek abortions are in extreme situations, such as rape or severe poverty. There is much more argument for either side, but it is obvious to me that abortion is morally justified in several cases, even if I think it is immoral in some.
Perhaps one of the more galling arguments put forth by Christian apologists is that of morality, claiming that the existence of morality is proof of their god. This is ridiculous for two reasons. First, if you use the Bible as a source for your morality, you are using the wrong source, as I illustrated in point 6. Second, morality has an entirely natural origin, as shown by the study of bonobos. For further info, look into the work of Frans de Waal – I’ll be leaning heavily on his research when I discuss this reason further.
The least moral Christian teaching, however, is the requirement of faith to avoid Hell. I hope I need not explain more than to point out that some people, such as myself, are apparently incapable of holding a conviction without evidence. Why would a god make me this way, then doom me to eternal torment for being this way?
This leads nicely to one of my other problems. If the Christian God were real, if He were omniscient, omnipotent, and wanted me to join Him in Heaven when I die, and if believing in Him was the first requirement for that, wouldn’t He give me everything I need to believe? And yet, I find absolutely no evidence, not evidence a convincing argument. I simply cannot believe, and if the Christian god were real, I would.
Indeed, it is difficult to tell that all Christians believe in the same god. There are so many disagreements between the over 40,000 denominations that one is forced to wonder how all-powerful that god could be. After all, I could probably write a book that is interpreted fewer than 40,000 different ways; why couldn’t god do that with the Bible?
The most classic reason to doubt Christianity is the problem of evil. I simply cannot believe that an all-loving being is watching over a world wherein child rape exists. I differentiate this from the problem of suffering, in that I could accept that some suffering is necessary even with an all-loving and all-powerful God in charge, but the unnecessary and ceaseless suffering of countless innocents in natural disasters worldwide is simply too much. Tsunamis, hurricanes, child cancer, parasites that eat a lamb’s brain as it slowly dies… how can anyone look at that and still believe in a loving deity capable of stopping such monstrosities?
I have one last historical argument. The character of Jesus in the gospels is possibly fictional, and certainly not as miraculous as described. Historical consensus is that the man did exist, but there are compelling arguments that he was a myth who was historicized, much like Hercules. In any case, most historians see all the contradictions among the various gospels as evidence that many of the events described never happened. Indeed, very little is left. However, this is an argument I am still studying.
My final main point is that Christianity causes harm. I cannot begin to list the harms that have come from following Christianity. From slavery, to child abuse (“Spare the rod, spoil the child”), to persecuting gays… These are not isolated incidents. They happen over, and over, and over. Why would a loving god allow such behavior from his earthly representatives?
I have many other reasons, most of which I plan to flesh out over the course of this blog. One argument of which I am particularly fond is what I call the Bored Pantheon Hypothesis, which shows that miracles aren’t good enough evidence to prove a specific supernatural being – they could just as easily show that a bored pantheon is messing with humans and making them think a certain religion is correct for the game of it.
One argument I have heard from a Christian is that Christianity is a properly basic belief. I will probably deal with it more fully in a later post, but my initial and immediate response is that nobody has ever come to believe Christianity all on their own. Christianity has only ever spread through the work of missionaries or soldiers.
My final thought is this: I do not believe in any god because I see no evidence of one. That’s the only argument I should ever need.