The introspection of ineffable feelings that leads to spiritual awakening was necessary in the evolution of Homo Sapiens. The privilege of ineffability belongs to no other living entity but us because we were the only ones who developed a mind-brain duality that then allowed us to ponder sacred and spiritual values that are culturally and geographically universal.
There must be truth to the idea that belief in the supernatural is embedded in the deepest sulci of our brain. Empirical evidence show that generally speaking humans with deep spiritual predisposition have differentiated neuronal connections in their corpus callosum and amygdala than humans with no spiritual connections at all. Could it be that during a human’s lifetime, separation from the spiritual to the purely physical/material predisposition could be traced to the development or non-development respectively of these neuronal connections?
Alfred Russel Wallace, an avid evolutionist (and together with Charles Darwin, co-elucidator of natural selection as it relates to the evolutionary process) diverged from the path of total materialism and naturalism when he concluded that natural selection alone was insufficient to account for a set of uniquely human characteristics the most obvious of which is the size and complexity of the human brain. Subsequently he proposed that some other entity had to be invoked, in order to explain the existence of a brain that could support the intellectual activities of humans in all cultures, time frames, environments and predicaments. That other entity he proposed was a supernatural one.