Abstract. Insights into the history and future of western civilization are found by applying information theory to the acoustical communication channel (ACC) of its worship spaces. Properties of the ACC have both influenced and reflected the choice of message coding (e.g., speech or music) at various times. Speech coding is efficient for acoustically dry ACCs, but hopeless for highly time-dispersive ACCs. Music coding is appropriate for time dispersive (reverberant) ACCs. The ACCs of synagogues, early Christian house churches, and many Protestant churches are relatively acoustically “dry” and thus well suited to spoken liturgies. The spoken liturgy, dominant in synagogues, was carried over to early Christian churches, but became unworkable in Constantinian cathedrals and was largely replaced with a musical liturgy. After a millennium, the cathedral acoustic was altered to suit the doctrinal needs of reformation churches with its renewed emphasis on the spoken word. Worship forms continue to change, and the changes are reflected in the properties of the ACC. The pulpits of electronic churches may be evolving into radio and television performance spaces and naves into worshipers’ living rooms.