In higher degrees (e.g., Royal Arch in York Rite), a subterranean chamber beneath the Temple holds the Ark of the Covenant and the Tetragrammaton (YHWH, the ineffable name of God). Enoch, a pre-Flood patriarch, hides divine secrets here to survive cataclysm. Rediscovered in the Temple's ruins, it symbolizes the preservation of ancient wisdom through ages, linking Freemasonry to antediluvian (pre-Noah) knowledge.
Mystically, this vault represents the hidden, secret, and forgotten place within where gnosis (divine knowledge) is buried and must be excavated through initiation.