The eye is the lamp of the body if your eyes are good, your whole body will be full of light.
the University of Arizona Center for Consciousness 2020 conference is this week. This study of consciousness connects in understanding ancient knowledge.
I am not endorsing (i have not taken but you would never know that) that anyone take these agents but understand that natural conscious experiences have a neurochemical correlate. Many ancient cultures had a very advanced understanding of consciousness. The Pineal gland which is better known to release the hormone melatonin inducing sleep also releases endogenous DMT. DMT is a known psychoactive consciousness altering compound that is known to have been used by ancient cultures. The egyptians likely used dmt from the acacia tree for conscious altering and expansion. The acacia tree was revered by the egyptians as the tree of life. It may have been used by other middle eastern cultures including the Hebrews. This sumerian relief likely depicts a pineal gland shaped pine cone dipped into the bucket by the tree of life. Likewise Amazonian Shamans have used dMT containing ayahuasca for at least 4000 years. DMT taken in these forms significantly alters the consciousness reducing external sensory awareness, a dissociation from self often out of body and enhancing spiritual like experiences. From a neuroscience point of view the brain wave eeg is markedly changed from a normal waking state showing an unusual back and forth pattern from theta waves associated with Rapid Eye Movement Sleep where dreams occur to the deep slow wave sleep Delta waves not associated with dreams or conscious activity but sometimes with nightmares. This is an interesting state of Paradoxical Waking state of consciousness indicating a more combined slow wave and rem asleep like state that since our brain makes this DMT endogenously may represent a natural state of conscious enhancement that may occur during prayer, meditation, fasting, chanting, dancing and other spiritual conscious enhancing focused experiences.