The Tree of Life is an arrangement of ten interconnected spheres (called sephiroth, Hebrew for ‘spheres’), which represent the central organizational system of the Jewish Kabbalistic tradition. The Tree of life is considered to be a map of the universe and the psyche, the order of the creation of the cosmos, and a path to spiritual illumination. The ten spheres represent the ten archetypal numbers of the Pythagorean system; they are connected by paths assigned to the twenty two letter-numbers of the Hebrew alphabet.
The Kabbalistic tree of life has evolved over time. Its basic design is based on descriptions given in the Sefer Yetsirah, or Book of Creation, and expanded upon in the enourmous Kabbalistic text Zohar, the book of Splendour. The ten Sephira, similar to the Norse tree of life, are divided into four realms:
Atziluth, the realm of the supernal, beyond which is the ain, or no-thing.
Beriah, the creative world, of archetypes and ideals.
Yetsirah, the world of formation.
Assiah, manifest creation, the material world.
The trees below represent the axis of the human chakras:
Another example, with kundalini serpent, from a nineteenth-century kabbalistic work: