In Le Corbusier’s religious buildings, space, light, sound, colour and rhythm are the key architectural elements which introduce visitor to a sense of inner harmony resulting from a state of spiritual transformation. This spiritual transformation can be most vividly experienced in the Ronchamp Chapel and the Monastery of La Tourette. The aim of this paper is to investigate the luminous environment of these two sacred structures through a comparative study which was conducted qualitatively and quantitatively. Much can be learned by studying Le Corbusier’s buildings which were built with daylight as the primary light source. Detailed analysis of his work would provide valuable insights and data which can be applied to the more routine design of the luminous environment.