Alta said:
From Wiki:
The term Tetragrammaton (from Greek τετραγράμματον, meaning "[a word] having four letters" [1]) refers to the Hebrew name of the God of Israel YHWH (Hebrew: יהוה) used in the Hebrew Bible.
Also worth remembering that the 4 letters in the tetragrammaton relate directly to the structure of the tarot.
YOD, HEH, VAU, HEH
FIRE, WATER, AIR, EARTH
KNIGHT, QUEEN, PRINCE, PRINCESS
FATHER, MOTHER, SON, DAUGHTER
WANDS, CUPS, SWORDS, DISKS
CHOKMAH, BINAH, TIPHARETH, MALKUTH
as well as lot of other stuff (star signs, quarters of the globe, seasons of the year etc..) Anything that divides into 4 you can relate to it really