In ancient times, and still today the symbolism of the cross (specifically the equal-armed cross in which each protrusion is equidistant from the center as shown in the image left) is indicative of the human desire to know & experience the unfolding mystery of life.
Primarily, the cross embodies the concept of unification between ethereal and material.
It was (still is) common for this symbol be worn at the level of the heart so that the wearer is intimate with the 4-fold concept the cross symbolizes which is: self, nature, knowledge, and God.
One of the simplest symbols, it represents several things to different cultures.
The cross was a symbol to the ancient Celts representing the meeting place of the Divine energies (at the cross-section).
In ancient Greece, the cross was an emblem of the four elements.
As a Native American symbol the cross has several connotations according to tribe. To the Hopi it is referred to as the “cosmic cross” with the four bars representing north, south, east & west correspond to the outermost points on the horizon where the sun passes through the year
In the ancient Middle East, the symbol also represents the four directions (north, south, east, west) and the four winds.
The symbolism of the equal armed cross is even seen in several cards of the Tarot deck such as the:
These images are derived from esoteric mystery schools of thoughts and in this perspective, the symbolism of the cross is generally counted as an aspect of balance.