What are the mystical meanings associated with the letters of the Tetragrammaton?

The first letter of the Tetragrammaton, the yod, is interpreted as representing "thought" or "idea" 1. It signifies an inaccessible light and primitive existence from which emanations proceed, carrying an efficacy to which no bounds are set 1. In symbolic lodge instruction, this letter is replaced by the letter G, whereas in advanced degrees the yod itself is retained within a triangle as a symbol of the Deity 1.

Taken as a whole, the four letters of the Tetragrammaton derive from the Hebrew substantive verb hayah, meaning "to be" 1. By combining the present, past, and future significations of this verb, the name designates God in His immutable and eternal existence 1. Rabbinical interpretations cited in Masonic scholarship, such as that of Menasseh Ben Israel, hold that permutations of these four letters yield twelve words, each a modification of the verb "to be," forming the name of His substance and essence 1.

Symbolically, the Ineffable Name represents the unutterable sublimity and perfection of divine truth emanating from the Supreme God 1. Within Masonic science, significant divine words are not used merely for recognition, but act as symbolic indices directing the candidate's progress from darkness to light and toward higher conceptions of truth 1.