H. P. Blavatsky

Vâch. To call Vâch “speech” simply, is deficient in clearness. Vâch is the mystic personification of speech, and the female Logos, being one with Brahmâ, who created her out of one‐half of his body, which he divided into two portions; she is also one with Virâj (called the “female” Virâj) who was created in her by Brahmâ. In one sense Vâch is “speech” by which knowledge was taught to man; in another she is the “mystic, secret speech” which descends upon and enters into the primeval Rishis, as the “tongues of fire” are said to have “sat upon” the apostles. For, she is called “the female creator ”, the “mother of the Vedas ”, etc., etc. Esoterically, she is the subjective Creative Force which, emanating from the Creative Deity (the subjective Universe, its “privation ”, or ideation) becomes the manifested “world of speech ”, i.e., the concrete expression of ideation, hence the “Word” or Logos. Vâch is “the male and female” Adam of the first chapter of Genesis, and thus called “Vâch‐Virâj” by the sages. (See Atharva Veda.) She is also “the celestial Saraswatî produced from the heavens ”, a “voice derived from speechless Brahmâ” (Mahâbhârata); the goddess of wisdom and eloquence. She is called Sata‐rûpa, the goddess of a hundred forms.

Source: H. P. Blavatsky, The Theosophical Glossary, art. Vach