Using insights from ethnographic studies of conservative Protestant congregations, the authors propose and test a refined conceptual model of theological conservatism that accounts for three key components of a theologically conservative worldview: (1. epistemology, a belief in the Bible as the inspired word of God, (2. ontology, assumptions about the pervasiveness of human sinfulness, and (3. soteriology, the conviction that salvation is made possible through a commitment to Jesus Christ. Structural equation modeling is used to examine the reliability and validity of this model across data sets and relativity to current approaches used in the study of religion. The proposed measure exhibits a substantial improvement for defining and interpreting the influence of religious conservatism across and within sociodemographic groups in contemporary American society. (Contains 4 tables and 13 notes.)