The internalization of religion is related to increased subjective well-being. However, relatively little is known about the process of religious internalization. In order to examine whether internalization of core religious behaviors show the same relationships with well-being as do overall measures of internalization, we studied the internalization of Sabbath keeping among a convenience sample of Seventh-day Adventist young adults on a Seventh-day Adventist university campus. In addition to replicating previous findings from more general measures of religious internalization with the internalization of a specific set of behaviors, we also developed a short instrument for measuring internalization of Sabbath keeping for use in further studies on the means of increasing internalization of Sabbath keeping, and on the role of internalized Sabbath keeping on individual and church health.