Through childhood and adolescence I had absorbed the intense Seventh-day Adventist religion of my family. I went to church schools from the beginning, only had friends from my church, and was forced to attend services with the fervor and frequency that only someone with a devout mother can understand fully.
I studied the Bible with interest but always found it a little boring (especially the Pauline epistles). If I had to read it, I would always go back to the books of Judges, Joshua, and the writings of the kingly epoch. I loved the stories of Jael and Siserah, of Joshua stopping the sun, of Saul and David. I loved to read about David collecting foreskins from the Philistines (and show it to my friends, giggling about how it was in the Bible). I was a believer in biblical inerrancy and a young-earth creationist just like all those around me. I was the best in my age group at Bible trivia (we called them Bible sword drills) to the point that our Sabbath School teachers would keep me from playing because it wasn't fair to the other kids.
In high school some of my friends were growing disillusioned with our church and I listened to their arguments but didn't find them compelling until I got to college. I wanted to go to medical school eventually, but I initially declared a major in Religion while taking all the science prerequisites needed for my premed aspirations. The second quarter of my freshman year, I took a class in Jesus and the Gospels. This was the first exposure I had had to higher literary criticism of the Bible and my exposure to the textual theories about the Gospels astonished me, and made me realize the all-too-human nature of the text. This also led me to investigate other German theories regarding the Bible including Graf/Wellhausen, which confirmed my concerns.
My study of religion abolished my faith in biblical inerrancy and I changed my major to biology.
I began to see strong evidence for evolution, even though all my professors were young earth creationists. In my junior year I started doing research into theories of taxonomy and their relationship to the creation/evolution debate. It was at this same time I took a course in cell and molecular biology.
It was fascinating to study up close the nuts and bolts that made cells function the way that they do, and to notice that not only was there no evidence of design, there was positive evidence against design. The endosymbiotic theory of Margulis had not yet been fully accepted, but it seemed to me to be the most compelling evidence against young-earth creationism that anyone could imagine.
The facts are this. Briefly, life is divided into several domains, bacteria, archaeans and eukaryotes. All the eukaryotes have a nucleus that separates their genes from the cell substance (cytoplasm). Animal and plant cells are all eukaryotes. Any eukaryote that can live in oxygen uses energy by oxidizing carbohydrates, such as sugars and starches.
All animal and plant cells that use oxygen burn it in a controlled fashion with an organelle called a mitochondrion. The mitochondrion has its own membrane. The mitochondrion has its own genome. The mitochondrion splits into two and divides by fission like a bacterium does. All plant cells that do photosynthesis do this photosynthesis using chloroplasts. Chloroplasts also have their own membranes and genomes and also split into two and divide by fission like bacteria do. The most curious part for me was this: there are cells that are eukaryotes but they do not have mitochondria or chloroplasts and they use energy by fermenting sugars and starches.
Fermentation happens in the cytoplasm of all eukaryotic cells but the burning of oxygen happens only in the mitochondrion. It became obvious to me that all multicellular life arose from a lucky symbiosis. When it became necessary to burn oxygen, eukaryotic cells were simply cobbled together out of two other cell types, one that fermented and one that oxidized. It seemed absolutely clear to me when I discovered this fact that life itself, down to its cellular level, was the product of accidents and was in fact an elaborate contraption. It was marvelous indeed in its function, but any appearance of design seemed to completely evaporate. After the scales lifted from my eyes it became clear what a confidence game young-earth creationism was. Life's function was entirely explainable by natural (as opposed to supernatural or vitalist) processes.
So I had lost my young-earth creationism and my belief in biblical inerrancy, but I still had the same family: a father and brother who were pastors, and a devout mother. My sister had abandoned religion very early in her life and I was worried that if I did so as well, it would hurt the structure of my family.
For many years I tried to pretend I was a “liberal” Christian, who believed in morality inspired by a remote, semi-deist God, but the more I studied works of theology and philosophy the more I realized there was no fact universally agreed upon, no doctrine beyond dispute, and no practice that didn't bring opprobrium from someone within Christianity and approval from someone else within Christianity. In short, “liberal” Christianity was a pseudonym for “humanism that won't scare your parents”.
Shortly after finishing my residency I was assigned to live in Turkey while I served time in the military. This experience clinched my conviction that religion was wholly man made. There I encountered the same false certainty, the same fervor for dogma, the same disputation over the meaning of holy texts, and the same lack of agreement that I found in Christianity, even the same platitudinous and empty bumper sticker sloganeering and the only thing different was that the religion was now that of Islam. Every argument that Christians make to convince you of the truth of their religion has a mirror image in Islam.
While living there, I was frequently asked what I believed. Since I was unable to defend Christianity, the existence of God, or any evidence of design in the universe, I decided to answer affirmatively, “I am an atheist.”