This dissertation attempts to address a perennial problem, i.e., the original understanding of the religious liberty provisions. To do so the author employs traditional primary source materials as well as cases interpreting the provisions from 1776 to 1900. The thesis of this study is that the religious freedom provisions were understood to embody a consensus in favor of liberty of conscience which held that: (1) civil rulers had no authority to define, compel observance or punish the breach of, religious duties; and (2) the individual must be left free to define and observe his religious duties so long as he did not threaten the civil order. The author argues that the Americans who ratified the First Amendment conceived of liberty of conscience and understood the religious liberty provisions primarily in terms of a set of beliefs and concepts expressed in terms of a religious strain of discourse, and based on a new understanding of scripture that had been worked out over hundreds of years prior to the Revolution. At the same time, however, this religious understanding of liberty of conscience overlapped with a more rationalistic, natural law and natural rights notion of liberty of conscience. The convergence of these two strains of discourse around the shared concept of liberty of conscience made possible the consensus principle that the religious liberty provisions were understood to embody by the Americans who ratified them. The author further argues that the case law interpreting the religious liberty provisions throughout the Nineteenth Century evidence the consensus posited by this study because they show courts struggling to distinguish religious and civil duties as the courts interpret the provisions, and, in this process, show a gradual unfolding of the implications of the consensus the provisions were understood to embody. Finally, the author also argues that this process of interpretation also demonstrates the preeminent influence of the Protestant Christian culture that engendered them and, in so doing, testifies to the preeminent influence of the religious strain of discourse in the understanding of the religious liberty provisions at the time they were ratified.