The eternal significance of a full-blown psychedelic experience is that it is the basis of all genuine religion. Broken down into its component parts, it is simple: remember the One; remember the Many; remember that which connects the One and the Many. In Christianity, this is expressed in terms of the Trinity: the One is the Father, the Many is the Holy Spirit and that which connects the two is the Son. An old hippy formula makes the same point: “lose your mind and come to your senses”.
“Losing your mind” is mysticism. This means that you forget the world and remember God. You pass through a “cloud of forgetting” and a “cloud of unknowing”. This is what I mean by the One. “Coming to your senses” is shamanism. This is about forgetting God and remembering the world. Emerging from the unity of consciousness in the One, the world of the senses is experienced as vibrant and fully alive. It is as if the world were born again, as if you were present at the moment of creation.
Between the One and the Many, “heaven” and “earth” is a person. This person is represented in religion as the archetype of perfect holiness: Christ, Krishna, Buddha. In order to maintain the beatific vision of the eternal One and the infinite Many, you must re-member the elements of personhood, will, heart, mind and soul, represented by the archetypes Warrior, Monk, Philosopher, King. In India these four elements are realized through karma yoga, bhakti yoga, jnana yoga and raja yoga respectively.
The psychedelic path is the religious path par excellence. Once you understand this, there is no limit to the spiritual progress you can make in this life.