From Sefer Yetzirah, chapter 1:1
With 32 mystical paths of Wisdom
engraved Y-h
the L-d of the Hosts, the G-d of Israel, the living G-d
King of the universe, E-l Sha-dd-ai
Merciful and Exalted
Dwelling in eternity
Whose name is Holy,
He is lofty and holy-
And He created His universe
with three books ( Sepharim ),
with numbers ( Sephar )
and with
communication ( Sippur).
Sefer Yezirah ("The book of creation"
) is the oldest and most mystical of all Kabalistic texts. The
first known reference to Sefer Yezirah dates back to the first
century, even that Abraham wrote it. In the first chapter it
describes how G-D created the world with 32 pathes- manifested
as the 10 digits ( the 10 sefirot, from saphor: "to number"
) and the 22 letters of the Hebrew alphabet.
To make this esoteric theory more accessible it has been arranged
into a geometric pattern. Over the centuries different sefirotic
systems have developed. The ten sefirot and their pathes are
also called the tree of life.