Seems to me it's just a particular slant on spiritual- / self-development. Unless one is religious and is told what to believe and how, they'll explore the worlds of spirit one way or another. Any tools can be used: magic mirror, meditation on various objects or questions, trying to get through the elemental worlds (fire is the easiest); sigils; vévés; prayer; pathworking; ceremonial.... One builds temples of the mind, crosses into different universes...

5D seems a fashionable approach with similar aims. A revamping of much that's been done over the millennia to bring it into a 21st C focus. The problem is always: is it another attempt to start a religion.
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