The letter D - symbolism
It is a letter of Phoenician origin. It is the fourth letter of the Greek alphabet - Delta - where the world began. In English and Hebrew it is the fourth letter. In the Cyrillic alphabet it is the fifth letter. The numerical value of the letter is also 4. It is the first letter of the Latin word Deus - God, the Greek word - Demiurge, Sanskrit - Deva (God). In Kabbalah Dalet means door.
The numeric value is four or Pythagorean Tetrad, the sacred Four, on which the Pythagoreans swore.
Tetragrammaton (or Tetraktos) is a form of the indescribable name of God. It is a means of four different aspects. It contains a period of ten days (the perfect number 10) and the primary triad (or triangle), linked to the divine monad. It is the sign of the completeness and perfection of creation and the operative part of our body and soul, the universe of music.
READ ALSO:
Letter A - stands for the sound, the great mystical power and acts of magic.
Letter C - is considered to be sacred because it contains the first letter of Christ.
Letter E - It is the eighth letter of the Greek alphabet. It includes all aspects of the soul.
Letter O - is present in all languages, and it looks like a disk of the sun, symbolizing perfection.