Principles of Sacred Buildings 9 Preface 10 Church Architecture Past and Present Rudolf Stegers Faith and ReligioTi in the Present Day / Histoiicism versus Modernity/The Church in the City/ Ecclesiastic Architecture from the 4th to the igth Century/The Development of Modern Church Architecture / At the Beginning of the 2ist Century /The Sacred and its Relevance for Churcli Architecture Today 38 Synagogue Architecture in the Recent Past and Present Roman Ho liens te in Synagogue Architecture in the 2Oth Century / Pioneering New Buildings from Louis Kahn toMario Botta/ The Design of the Synagogue Space/A Theory of Synagogue Design / Architectonic Symbols in Germany /Tradition over Experimentation in the United States 46 Mosque Architecture Past and Present Negar Hakim The Formation and Expansion of Islam / The Mosque as the Centre of Religious Life / The Four Types of Mosques / 20th-century Mosque Architecture in the Islamic World / 20th-century Mosque Architecture in the Nations of the Diaspora /The Spatial Programme and Arrangement of Modern-Day Mosques 54 Acoustics in Sacred Buildings Dorothea Baumann and Christina Niederstatter The Sound of Space as a Symbol of the Sacred/Architectural Acoustics-The Conflict between Resonance and Clarity / Sound and Sound Propagation / Geometric Analysis / Reflection and Diffraction / Reverberation Time and Absorption / The Number of People / Materials / Special Aspects of Acoustics in Sacred Spaces /Acoustic Analysis 60 Light in Sacred Buildings Eva-Maria Kreuz Light in Churches / Light in Synagogues / Light in Mosques