“This testimony from an unwilling witness shows again the identity between the ancient religions as to their secret doctrine. The Gayatri metre, for example, consists of thrice eight syllables, and is considered the most sacred of metres. It is the metre of Agni, the fire-god, and becomes at times the emblem of Brahma himself, the chief creator, and “fashioner of man” in his own image. Now, Pythagoras says that “The number eight, or the Octad, is the first cube, that is to say, squared in all senses, as a die, proceeding from its base two, or even number; so is man four-square or perfect.” Of course few, except the Pythagoreans and kabalists, can fully comprehend this idea; but the illustration will assist in pointing out the close kinship of the numerals with the Vedic Mantras.
The chief problems of every theology lie concealed beneath this imagery of fire and the varying rhythm of its flames. The burning bush of the Bible, the Zoroastrian, and other sacred fires, Plato’s universal soul, and the Rosicrucian doctrines of both soul and body of man being evolved out of fire, the reasoning and immortal element which permeates all things, and which, according to Herakleitus, Hippocrates, Parmenides, is God, have all the same meaning.
Each metre in the Brahmanas corresponds to a number, and as shown by Haug, as it stands in the sacred volumes, is a prototype of some visible form on earth, and its effects are either good or evil. The “sacred speech” can save, but it can kill as well; its many meanings and faculties are well known but to the Dikshita (the adept), who has been initiated into many mysteries, and whose “spiritual birth” is completely achieved; the Vach of the mantra is a spoken power, which awakes another corresponding and still more occult power, each allegorically personified by some god in the world of spirits, and, according as it is used, responded to either by the gods or the Rakshasas (bad spirits). In the Brahmanical and Buddhist ideas, a curse, a blessing, a vow, a desire, an idle thought, can each assume a visible shape and so manifest itself objectively to the eyes of its author, or to him that it concerns.
Every sin becomes incarnated, so to say, and like an avenging fiend, persecutes its perpetrator. There are words which have a destructive quality in their very syllables, as though objective things; for every sound awakens a corresponding one in the invisible world of spirit, and the repercussion produces either a good or bad effect. Harmonious rhythm, a melody vibrating softly in the atmosphere, creates a beneficent and sweet influence around, and acts most powerfully on the psychological as well as physical natures of every living thing on earth; it reacts even on inanimate objects, for matter is still spirit in its essence, invisible as it may seem to the grosser senses. So with the numerals.”
H. P. Blavatsky
The Mark Of God: Understanding Your "I AM Presence" 