The project, located in the Monsanto´s woods near Lisbon, is set to develop the preliminary program for a Roman Catholic Apostolic Church. The concept is based on the confrontation betweeen light-darkness/ transparency-enclosure, and the very sacredness of the place is determined by these two conflicting concepts. The proposal is developed in several volumes, multiplying interior and exterior paths, defining spaces, uses and sensations. To access the church building, generator of the whole, the user must do so through a maze characterized by darkness, thus purifying his soul before entering the sacred space, being "guided" through tears of light and the sound of water, which determine the different routes. The Labyrinth is an archetype, a divine mark found in all religious traditions throughout the world. It offers several routes to be followed and is a tool that encourages meditation and refers to the experience of transformation. The route is intuitive and the labyrinth offers the believer what he needs to find the prospect of a new level of consciousness, where light and water exert a guide function, like the ball of wood of Euclid, guiding the user through the darkness. Accessing through this labyrinth the user reaches the Church, that symbolizes the light. The building consists of a glass box "inside" a slatted wooden box, made in pine strips, transposing into the building the color match dichotomy and the lightness / darkness of the woods. The choice of glass to enclose the entire space was due to maximize the use of natural light and an ongoing dialogue with the landscape through reflections and transparencies.