John is a very inquisitve character; he has an insatiable thirst for more knowledge. In the story itself, he mentions his drive and hunger for knowledge over and over again. It is his intense desire to gain wisdom, knowledge and understanding that drives him to the place of the gods. He knows that it is forbidden, but, he feels that on his spirit walk, as a priest's son, and with good intentions, he is justified in pushing the boundaries of the old rules a bit.
During his entire journey, is is cautious and wary about what he is doing, and watches and waits for potential bad omens, or warnings against going to the city. He receives none; in fact, he feels like there are signs prompting hiim there. He sees "a white fawn...a very great sign," and feels like it is the gods giving him their blessing to go forward. As he enters the city, he is "afraid, afraid," but keeps going because "my hunger for knowledge burned in me." That hunger for knowledge keeps him going until the very end. All throughout the story, he kept breaking through barriers, driven by his desire to know the things that he "did not understand," and to fill his need for knowledge and wisdom. His desire for knowledge is satisfied as he learns the great truth that the gods "were men" just like him. Because of his driving need for knowledge, he discovers truths that will help his tribe advance and progress. I hope that those thoughts helped; good luck!