In summary, it is the Old Testament that interested Algernon Sidney in his refutation of Filmer. His stated reason is that, like Roman history, the sage of the Hebrews "is best known to us." More particularly, a distinct inclination toward the Covenant theology of the Pentateuch, especially the codes of Deuteronomy is noticeable. While it was shown previously that Sidney used the Greeks and Romans to buttress his ideal of virtue, in the covenants of the Old Testament his objective was to justify the essence of the contract. Indeed, the link with covenant theology is too close to ignore. To put it another way, the ancient Hebrews were practicing and symbolically celebrating--via their political literature--what at least one seventeenth-century political thinker identified as the social contract.--The Discourses of Algernon Sidney, By Scott A. Nelson
Likewise, Sidney read Calvin to favor deposing Princes through abdication, just as Witherspoon did:
Significantly, the topic in this section has to do with whether people are at liberty to depose their princes. Sidney ascribed a positive endorsement to both Calvin and Bellarmine, and openly proclaimed allegiance with them against the likes of Filmer.