The first chapter of God Is Not Great covers Hitchens’s early life and his transformation from a studious religious student to a passionate non-believer. The book opens with a warning to readers, stating that anyone who tries to identify something wrong with the author for holding the opinions found throughout the book is by extension degrading his favorite childhood teacher, Mrs. Jean Watts.

Hitchens explains that his early schooling included Church of England religious lessons. The children were regularly assigned a verse of scripture to analyze, an activity Hitchens reports enjoying and excelling at. It taught him critical analysis at an early age, even before he began to doubt the religious lessons. The spark of doubt came from one specific lesson by Mrs. Watts, in which she asked the children why grass is green. Rather than giving a scientific answer, she stated that God made grass green because it is the most restful color to human eyes, and prompted them to imagine how strange it would be if the grass were orange, purple, or any other color. Hitchens claims that, even as a young boy, he immediately saw the flaw in this argument. Although he knew nothing about the science of photosynthesis or chlorophyll, he could feel in his gut that this explanation was an oversimplification of the natural world.