In addition to the colors of the spectrum there are a vast number of vibratory color waves, some too low and others too high to be registered by the human optical apparatus.
In the original symbolism of the Christian Church, colors were of first importance and their use was regulated according to carefully prepared rules. Since the Middle Ages, however, the carelessness with which colors have been employed has resulted in the loss of their deeper emblematic meanings. In its primary aspect, white or silver signified life, purity, innocence, joy, and light; red, the suffering and death of Christ and His saints, and also divine love, blood, and warfare or suffering; blue, the heavenly sphere and the states of godliness and contemplation; yellow or gold, glory, fruitfulness, and goodness; green, fecundity, youthfulness, and prosperity; violet, humility, deep affection, and sorrow; black, death, destruction, and humiliation. In early church art the colors of robes and ornaments also revealed whether a saint had been martyred, as well as the character of the work that he had done to deserve canonization.
According to esoteric philosophy, blue is the true and sacred color of the sun. The apparent orange-yellow shade of this orb is the result of its rays being immersed in the substances of the illusionary world.
The ancients conceived the spirit of man to correspond with the color blue, the mind with yellow, and the body with red. Heaven is therefore blue, earth yellow, and hell–or the underworld–red.
The theory so long held of three primary and four secondary colors is purely exoteric, for since the earliest periods it has been known that there are seven, and not three, primary colors, the human eye being capable of estimating only three of them. Thus, although green can be made by combining blue and yellow, there is also a true or primary green which is not a compound. This can he proved by breaking up the spectrum with a prism. Helmholtz found that the so-called secondary colors of the spectrum could not be broken up into their supposed primary colors. Thus the orange of the spectrum, if passed through a second prism, does not break up into red and yellow but remains orange.
To the Rosicrucians, Alchemists, and Illuminati, the cross was the symbol of light, because each of the three letters L V X is derived from some part of the cross.
The cross is also highly revered by the Japanese and Chinese. To the Pythagoreans the most sacred of all numbers was the 10, the symbol of which is an X, or cross. In both the Japanese and Chinese languages the character of the number 10 is a cross. The Buddhist wheel of life is composed of two crosses superimposed, and its eight points are still preserved to Christendom in the peculiarly formed cross of the Knights Templars, which is essentially Buddhistic. India has preserved the cross, not only in its carvings and paintings, but also in its architectonics; a great number of its temples–like the churches and cathedrals of Christendom–are raised from cruciform foundations.
In his article on the Cross and Crucifixion in the Encyclopædia Britannica, Thomas Macall Fallow casts much light on the antiquity of this ideograph. “The use of the cross as a religious symbol in pre-Christian times, and among non-Christian peoples, may probably be regarded as almost universal, and in very many cases it was connected with some form of nature worship.”