The Dutch architect and monk, Dom Hans van der Laan (1904–1991) leaves us with a legacy of architectural writings and realisations arising from his search for fundamental principles of architecture. His 1977 manifesto Architectonic Space aims to combine spatial philosophical concepts with practical design tools [1, 2]. The book is a series of fifteen lessons linking concepts, such as the relationships of inside-outside or mass-space, to his proportional series which he refers to as the Plastic Number. This article aims to offer an understanding and critical assessment of Dom van der Laan's poetics of order by unravelling how his buildings are made and how they are perceived [3]. I focus on the case study of the Jesu Moder Marias Convent in Tomelilla, Sweden.