Аннотация:During the 1970s the intellectual and cultural climate in Flanders increasingly matured, also in the field of architecture. This fledgling cultural renaissance was fed to a remarkable extent by intellectuals with a religious background who chose to reorient their careers outside the Church. This article focuses on one of those clerics-turnedpublic intellectuals: sociologist and former Passionist Sieg Vlaeminck (1933–2011), who during the 1970s advocated a scientifically grounded approach of the built environment, labelled woonecologie . His life trajectory unites (1) a plea for sciences, embodying a trend towards scientification, (2) a public voice acknowledging architecture’s societal relevance and (3) a first-hand witness of and contributor to a growing secularization of religious culture. This paper traces the transfiguration of Vlaeminck’s religious vocation into an architectural engagement, in order to offer one way of grasping how architectural culture of the 1970s benefited from the secularization that affected the Catholic Church.