This thesis argues that a theory of religion can be constructed upon a close reading of Jürgen Habermas' The Theory of Communicative Action. While influential in many diverse fields of scholarly research, Habermas' thought has been relatively neglected in the area of religion, especially around the time of the above publication. I address this gap in research by (a) considering Habermas' main arguments in terms of rationality, society, and communication, (b) tying these to his engagements with the work of Max Weber and Émile Durkheim, then (c) formulating a Habermasian theory of religion, before finally (d) offering both a critique and suggestions for future research.