The following passage illustrates how the mystical mind works when it decides to address the process of divine revelation,which is to say the moment when it leaves the unknown to make itself manifest to men, precisely at the beginning of Creation :

The Beginning of Creation
When the King conceived the ordaining (of the world)
He engraved engravings in the luster on high
A blinding spark flashed
within the Concealed of the Concealed
from the mystery of the Infinite,
A cluster of vapor in formlessness
Set in a ring,
Not white, not black, not red, not green,
No color at all.
When a band spanned,
It yielded radiant colors.
Deep within the spark gushed a flow
Imbuing colors below,
Concealed within the concealed of the mystery of the Infinite.
The flow broke through and did not break through its Aura.
It was not known at all.
Until, under the impact of breaking through,
One high and hidden point shone.
Beyond that point, nothing is known.
So it is called Beginning.
The first command of all.

Zohar I, 15a

The passage mentions a number of notions - the king, the beginning, veiling - that are full of significant symbols that nourish the mystical imagination. The most basic, common concepts in Zohar mysticism are the Ein-Sof, the In-finite, and the Sefirot, or the spheres. Ein-Sof generally designates the hidden and unknowable side of God, the hidden and perfect root of reality which can neither be named nor imagined although it can be described and which is often considered to be the cause of causes, revealing itself only to the mystical intution of rare initiates. The ten spheres, or Sefirot, are like the steps or stages by which God reveals himself beyond the In-finite. There is some Biblical explanation of these spheres in the corpus symbolicum which the kabbalist must read attentively and with devotion. Each letter has a mystical meaning and can reveal one aspect of God and of His work. Some commentators believe that the first Sefira, Keter Elyon or or the Heavenly Crown symbolizes the void from which Creation emanates. Hokhma or Wisdom, the second letter, represents the thought which commands the order of creation, the root or unexpressed essence of all things, the root of roots. The third letter, Bina, or Understanding, determines the differentiation and individualization of things. The fourth Sefira, Hessed, is love, the fifth, Guevura or Din can be translated as Power or Judgment. Rahamim or Charity or Tiferet, Beauty, the sixth, comes from the mixture of the two prior Sefirot. The seventh, Netsah or Permanence, the eight, Hod or Majesty, the ninth Yessod or Foundation in which the preceding Sefirot join to designate God's continuous procreativity in the universe. The tenth and last Sefora is Lakhut or Kingdom. Chekhina or Presence designates God's immanence in Creation and the Community of Israel, "eyeless beauty," exiled by God because of original sin, the messianic era announcing the reinstatement of its harmonious unity with and in God. Kabbalistic literature often uses many different metaphors to attempt to clarify the ten Sefirot and their relationship with the Ein-Sof. Gershom Scholem presents the metaphor of the tree in the following terms :

The ten Sefirot constitute the Mystical Tree of God or the Tree of Divine Power. Each represents a branch whose common root is unknown and unknowable. But Ein-Sof is not only the hidden Root of all roots, it is also the sap of the tree and each branch represents an attribute which exists thanks to the Ein-Sof, to hidden God. This tree of God is also the skeleton of the universe running through creation and stretching its branches in all its ramifications. All created things found in the world exist only for this reason: something of the power of the Sefirot lives and acts through them.

Gershom G. Sholem, The Currents of Jewish Mysticism