I've been reading a fascinating book, "Why God Won't Go Away" by Andrew Newberg M.D. and Eugene D'Aquili, M.D. Ph.D. Newberg is both a physician and an instructor of religious studies, Dr. Aquili (now deceased, he died before this book of his research was published) was a distinguished psychiatrist.
The book is about the biological and neurological basis for belief in God. They studied the brains of people with various imaging systems while they were undergoing transcendent state induced by prayer, ritual, chanting, meditation and found profound brain changes that explain the state that most find difficult to describe in literal terms.
Basically, the part of the brain that defines self and how the self is oriented physically in the world around us undergoes an interesting and distinct change during these activities. It's functioning slows considerably and a person literally is in a state where they lose their sense of connectedness with the world around them and experiences that "connected to the universe/God/the infinite" however they term it. That is just one of many brain changes that occur during transcendent, mystical or religious experiences, regardless of type of practice. The brain of a Franciscan nun praying reacts exactly like a Buddhist practicing transcendental meditation. The brain of a person hearing an uplifting Christian sermon or music reacts exactly like that of a Pagan during a blessing ritual.
Of course, that does nothing to prove God (or gods) exists, literally, but it goes a long ways towards explaining WHY people believe in the mystical, the supernatural and the divine.
My favorite exerpt from the book:
" The best that science can do is give us a metaphorical picture of what's real, and while that picture may make sense, it isn't necessarily true. In this case, science is a type of mythology, a collection of explanatory stories that resolve the mysteries of existence and help us cope with the challenges of life. This would be applicable even if material reality is, in fact, the highest level of reality, because despite science's preoccupation with objectively verfied truth, the human mind is incapable of purely objective observations. All our perceptions are subjective by their nature, and just as there's no way to peek inside Einstein's Watch (he alludes to the metaphor used by Einstein that when explaining reality, we are like a man peeking inside a permanently closed watch, we deduce what is going on inside by the clues, but can never peek inside) there's no way we can slip free of the brain's subjectivity to see what's really there. All knowledge, then, is metaphorical, even our most basic sensory perceptions of the world around us can be thought of as an explanatory story created by the brain.
Science, therefore is mythological, and like all mythological systems of belief, it is based on a foundational assumption: All that is real can be verified by scientific measurements, therefore, what can't be verified by science isn't really real.
This kind of assumption, that one system is the exclusive arbiter of what is TRUE, makes science and religion incompatible. If Absolute Unitary Being does indeed exist then science and religion find themselves in a paradoxical situation: The more literally we take their own foundational assumptions, the deeper they are in conflict with each other, and the further they fall from ultimate reality. But, if we understand the metaphorical nature of their insights, their incompatibilities are reconciled, and each becomes more powerfully and transcendentally real."
In other words, just because something is a metaphor, or non literal does not make it untrue or unreal. Because of the natural construction of our human brains, metaphor is the highest and most real, even the most "true" form of thinking, regardless of what it is applied to.
Realizing that gives power to both the spiritual metahpor and the scientific one.