Merkaba: ( or Merkava)is a Hebrew word which means 'Chariot' or 'to ride an animal, in a chariot' It is used in the Bible (Ezekiel 1:4-26) to refer to the throne-chariot of God, the four-wheeled vehicle driven by four Cherubim, each of which has four wings and four faces (of a man, lion, ox, and eagle). Four means 'time' in alchemy.

It is the divine light vehicle used by the Masters to connect with and reach those in tune with the higher realms. The Mer-Ka-Ba is the vehicle of Light mentioned in the Bible by Ezekiel. "Mer" means Light. "Ka" means Spirit. "Ba" means Body. Mer-Ka-Ba means the Spirit / Body surrounded by counter-rotating fields of Light, (wheels within wheels), spirals of energy as in DNA, which transports Spirit / Body from one dimension to another.

The earliest merkabah speculations were exegetical expositions of the prophetic visions of God in the heavens, and the divine retinue of angels, hosts, and heavenly creatures surrounding God. The earliest evidence suggests that merkabah homiletics did not give rise to ascent experiences - as one rabbinic sage states: "Many have expounded upon the merkabah without ever seeing it" (Tosefta' Megillah 3[4]:28).

The Talmudic interdictions concerning merkabah speculation are numerous and widely held. Discussions concerning the merkabah were limited to only the most worthy sages, and admonitory legends are preserved about the dangers of overzealous speculation concerning the merkabah. The sages Rabbi Yochanan Ben Zakkai (d. ca. 80 CE) and later, Rabbi Akiva (d. 135) were deeply involved in merkabah speculation. Rabbi Akiva and his contemporary Rabbi Ishmael ben Elisha are most often the protagonists of later merkabah ascent literature.

Beyond the rabbinic community, Jewish apocalyptists also engaged in visionary speculations concerning the divine realm and the divine creatures which are remarkably similar to the rabbinic material. A small number of texts unearthed at Qumran indicate that the Dead Sea community also engaged in merkabah speculation. Recently uncovered Jewish mystical texts also evidence a deep affinity with the rabbinic merkabah homilies. Recently, considerable scholarly attention has been paid to the use of merkabah themes in early Jewish-Christian circles.

The merkabah homilies eventually consisted of detailed descriptions of multiple layered heavens (usually seven in number), often guarded over by angels, and encircled by flames and lightning. The highest heaven contains seven palaces (hekhalot), and in the innermost palace resides a supreme divine image (God's Glory or an angelic image) seated on a throne, surrounded by awesome hosts who sing God's praise.

When these images were combined with an actual mystical experiential motif of individual ascent (paradoxically called "descent" in most texts) and union is not precisely known. By inference, contemporary historians of Jewish mysticism usually date this development to the third century CE. Again, there is a significant dispute amongst historians over whether these ascent and unitive themes were the result of some "foreign," usually Gnostic, influence, or a natural progression of religious dynamics within rabbinic Judaism.