For those who are unfamiliar with my journey, I began my studies pursuing independent readings into folklore. Later I changed direction a bit and pursued studies in narratology, storytelling, and later narrative analysis.  It is these related areas of knowledge that has furnished me with a deeper understanding of how religions like Judaism and Christianity originate.
According to secular theories, religion originates due to people's fear and a need for security in an insecure world (Robinson, 2014). Others talk about natural selection favouring human beings with a God gene to help to create a more social cohesive group or society (Wade, 2009). However, my studies in folklore and narratology have helped me see a new perspective (outside of faith-based theories) for how religions like Christianity and Judaism originate.
Let us begin by using the concept of a "meta-narrative" as a metaphor for religion. According to Aryes (2008), a meta-narrative is a narrative about narratives or a narrative above narratives. Narrative itself is often seen as being based on real or lived experiences. Labov (1972) defined narrative as the recapitulation of experience. Benjamin (1984), on the other hand, states that the storyteller produces stories from the raw material of experience. Religion, like narrative, is born from real characters and experiences, which are structured into a coherent telling for transmission to others. After all, religious narratives are but meta-narratives, bringing together many characters, experiences and real events, into a coherent unified structure that interprets and provides some sense-making across various fragmented (or smaller) narratives.
You find this in the Passover narrative of the birth of Jewish identity and cultural independence. It begins with characters (Pharaoh and Moses) and key events (such as how the Jews escaped Egypt and established a home in Canaan). You also find this in Christianity with the character of Jesus, who inspires a band of followers to establish a new group (and religious) identity. Religion, unlike some mythologies, are based on real geographic settings and are either based on or inspired by real characters and events. These are not fables devised by wild imaginations, but originate from real characters that have real experiences in real places and who share these experiences in the form of narratives with others.
Over time, others may add to the narrative or take away from the narrative. This is especially the situation with oral narratives. However, writing narratives cause them to become more fixed, albeit dis-placing contextual information about the narrative. With oral narratives, the storyteller can give facial expressions and other gestures to help communicate how the narrative should be understood or the intended meaning of his or her words. In addition, the storyteller's audience can ask for clarification and the storyteller can point out locations and show where the actual narrative or event unfolded (especially if the storyteller is in the geographic area of the narrative). The written narrative actually decontextualizes the narrative and removes it from a set location and a particular storyteller in order to make it more transportable over distance and time.
Hence, once we understand these ideas, we can see how religious narratives are not fictional creation or construction of imaginary characters or events. Rather, religion is more mixed-fiction (if not non-fiction), drawing on the real as well as using the imagination and sense-making faculties to produce a coherent and unified meta-narrative to structure the experiences of several characters and events over time. Hence, understanding religion is not just about looking for a gene or examining the function of religion in societies. It is more than that. It is about understanding narrative knowledge, storytelling and narrative practices. I find that this is hard for a secular society that depends on science and logic driven by quantitative data and methods for producing knowledge, while at the same time devaluing the personal experience and narrative-based knowing.
 - I see folklore studies as a broader field of study that includes the study of oral lore and narratives that are told by ordinary folk.
Aryes, L. (2008). Meta-narrative. In L. M. Given (Ed.), The Sage Encyclopedia of Qualitative Research Methods (pp. 508–509). Thousand Oaks, CA: Sage Publications. doi:10.4135/9781412963909
Benjamin, W. (1969). Illuminations, ed. and with an Introduction by Hannah Arendt. Trans. by Harry Zohn. New York: Schocken Books.
Labov, W. (1972). Language in the inner city: Studies in the Black English vernacular. Philadelphia: University of Pennsylvania.
Robinson, B. A. (2014). Some theories on the origins of religion. Religious Tolerance.org: Ontario consultants on religious tolerance. Retrieved from http://www.religioustolerance.org/rel_theory1.htm
Wade, N. (2009, Nov. 14). The evolution of the God gene. The New York Times. Retrieved from http://www.nytimes.com/2009/11/15/weekinreview/12wade.html?_r=0