People in the Gothic era thought of their cathedrals as a symbol or image of the "City of God" built on earth. Intellectual thinking and religious education was moving beyond just monasteries and religious pilgrimage sites into larger populated cities where universities started to flourish. Cathedrals were being built that "reached" for the heavens. Abott Sager, known for rebuilding the Saint-Denis Cathedral in France, wrote what was to become an insight to the inspiration for building of these great Gothic cathedrals. The "costly furnishings and light filled space caused him to delight in the beauty of the house of God." (Gardner p. 361). This marked a beginning of elaborate stained glass windows that allowed light to permeate into the churches.
The light weight of the developing rib vault allowed ceiling to soar higher and higher. Thus, the heightened outer walls became a perfect place to display narratives and teachings of the Bible in stunning color and light of the stained glass. The stained glass in most cases actually reduced the pure light of entering the church as it transformed the light into dramatic and colorful light that illuminated the religious messages that the religious leaders wanted to teach the public. The importance of the narrative stained glass became so important that churches were built with as little bulky wall possible and was replaced with intricate stone, lace-like patterns which served as the framework for the elaborate stained glass windows. This was a framework that would still provide the lessening support needed for the rib vaulted ceilings, but became a larger part of the window artwork. Thus walls were not merely covered with colorful paintings and art the window artwork actually replaced much of the walls. The light was transmitted and transformed by the windows into the places of worship. The belief was that that the light illuminating the cathedrals would enlighten the diverse congregations and pilgrims.
The height and "reach" to the heavens continued to grow higher and higher as the period progressed. This made the structures more prominent on their landscape and the visibility extended the "reach" to further distances and people. The towering height over the surrounding building in turn would allow more and more light to illuminate in high dramatic form the scriptures to enlighten the masses.