why is the Royal Arch degree set in a subterranean vault

Wilmshurst takes the subterranean vault in the Royal Arch as a symbol of the inner depths of human consciousness, into which the candidate must descend to achieve spiritual rebirth and self-realization 1. In his interpretation, entering these subterranean depths represents an inward journey where subjective perceptions are explored and refined 1. The candidate's subsequent return from the vault to the surface symbolically achieves an extroversion of those perceptions, resulting in the unification of all his component parts and the illumination of his whole nature 1.

Through this symbolic transition from the depths back to light, the candidate achieves not merely illumination by the Divine Light, but complete identification with It 1. Wilmshurst likens the state reached in this subterranean symbolism to the Beatific Vision or cosmic consciousness, wherein the candidate realizes that the vast universe outside himself is mirrored within his own internal nature 1. The subterranean setting thus provides the symbolic stage for the ultimate consummation of the Masonic quest, restoring the candidate to light with an expanded spiritual awareness 1.

The legend of the subterranean vault derives primarily from Talmudic and Rabbinical traditions rather than recorded history 2. According to Rabbinical accounts, workmen preparing the foundations of the First Temple discovered a subterranean vault supported by seven arches 2. Later Rabbinical tradition relates that King Josiah commanded the Levites to hide the Ark of the Covenant within this secret chamber to save it from impending destruction, where it lay hidden under rubbish until discovered by the workmen of Zerubbabel during the building of the Second Temple 2. A related tradition attributes the vault's construction directly to King Solomon, who built it as a secure depository for secrets connected to his palace by a subterranean passage, only for its entrance to be buried during the destruction of Jerusalem until a keystone was later uncovered 2.

A similar narrative tradition appears in accounts of the Emperor Julian's fourth-century attempt to rebuild the Temple at Jerusalem 2. In that account, a stone displaced at the foundation exposed a square subterranean cave in the rock; a workman lowered by rope into the vault discovered a sacred text preserved on a column rising above the water 2.

Beyond specific Rabbinical and historical legends, the symbol of the secret vault reflects an ancient pattern of subterranean initiation 2. In the ancient mysteries, candidates descended into underground structures to represent a symbolic descent into the grave, through which alone divine truth was to be recovered 2.