In Kabbalah, a reference to the sephirah Yesod of the Tree of Life (Kabbalah). When you place the Tree of Life over your body, you see that Yesod is related to your sexual organs.

"The Ninth Sphere of the Kabbalah is sex." —Samael Aun Weor, The Perfect Matrimony

The Ninth Sphere also refers to the lowest sphere of the inferior worlds (Hell, Klipoth).

"The great Master Hilarion IX said that in ancient times, to descend into the Ninth Sphere was the maximum ordeal for the supreme dignity of the Hierophant. Hermes, Buddha, Jesus Christ, Dante, Zoroaster, Mohammed, Rama, Krishna, Pythagoras, Plato and many others, had to descend into the Ninth Sphere in order to work with the fire and the water which is the origin of worlds, beasts, human beings and Gods. Every authentic white Initiation begins here." —Samael Aun Weor, The Aquarian Message


"We should not mistake the Truth with opinions. Many think that the Truth is this or that, or that the Truth is within this or that book, or within this or that belief or idea, etc. Whosoever wants to experience the Truth should not mistake beliefs, ideas, opinions and theories with that which is the Truth. We must experience the Truth in a direct, practical and real manner; this is only possible in the stillness and silence of the mind, and this is achieved by means of meditation."