Sermons in Stone
The initiatic, alchemical, templar, gnostic christos knowledge encoded into the building itself, into the cathedral/temple.
“Building, or creating, is the centerpiece of Freemasonry, and it was said for generations that the origin of the fraternity was to be found in the medieval building guilds. Oral traditions state that Freemasons, or their predecessors, were said to have possessed some occult secret carried back from Jerusalem or elsewhere and encapsulated it into the iconography of the great Gothic cathedrals. This theme was particularly expounded upon by the mysterious twentieth century French alchemist Fulcanelli in The Mystery of the Cathedrals, wherein he states that the entire alchemical corpus can be found in the stonework of cathedrals such as Notre Dame and Chartres.” - The Path of Freemasonry, Mark Stavish
Gothic cathedrals encode the Gnostic body theology - Notre Dame and other cathedrals are laid out as the body of Mary/Sophia: baptismal font at navel, choir at lungs, priest speaks from heart, sacrament kept at forehead. Leaving through the door = being born as Christ, achieving Christos consciousness.
Fulcanelli - The Mystery of the Cathedrals

“Not so long ago, architecture was typically the highest and most complete artistic expression of a sophisticated civilization. It provided the framework within which the other arts forms manifested. It was where the lion’s share of any given society’s creativity was directed; the architecture expressed and enshrined the soul. In fact, if we had no written history at all, we would be able to get a very good idea of the living essence of any given civilization simply by looking closely at where its creative energy is expended: Ancient Egypt’s creative energy went into its temples, pyramids, and tombs; Rome’s went into its roads, massive civic projects, and coliseums; our today goes into an elaborate missile defense system and disposable products designed to feed our materialistic, consumer-driven culture.” - John Anthony West, in the foreword to The Return of Sacred Architecture: The Golden Ratio and the End of Modernism by Herbert Bangs
St. Apollinaris window at Chartres creates a 3-4-5 triangle on St. John's Day - On June 24th, light passes through a hole in the window dedicated to Apollo (the sun god) and strikes a brass peg in a crooked floor tile, forming a perfect Pythagorean triangle
Alchemical and Hermetic symbols are carved openly on cathedral facades - Notre Dame displays salamanders on fire (representing stable salt through calcination), Hermes with caduceus, an alchemist in a Phrygian cap on the roof, and pelicans (alchemical vessels) - none of which are biblical figures.
The Templar Masons were the only ones allowed to wear white gloves - The 1268 Templar Rule specifies only chaplains (handling the Eucharist) and Templar Mason Brothers could wear leather gloves, establishing the special status of the building guild.
Rosslyn Chapel contains cymatic patterns 400 years before their "discovery" - Angels carved playing specific musical notes have corresponding geometric sand patterns (cymatics) carved above them - proof that Templar/Hermetic knowledge of vibrational creation predated modern science.