It is the contention of this paper that a better understanding of Locke’s political theory can be gained by comparative study of his later religious text, The Reasonableness of Christianity alongside his Two Treatises of Civil Government. These texts contain notable parallels and contrasts which we describe in this article. Specifically, Locke’s critique of Robert Filmer’s patriarchalist theory of absolute monarchy both address the implications of the biblical Fall from an original state of human kind in the biblical account of the Garden of Eden. Locke’s account of natural human equality, including gender equality in his Second Treatise then relies upon his prior demolition of the claim that the Fall lead to the establishment of a legitimate form of political domination and this account is consistent with and effectively reinforced by the emphasis on free will in his later religious writings.