Strauss, Leo, "Marsilius of Padua," in History of Political Philosophy, edited, L. Strauss and J. Cropsey (Chicago: University of Chicago Press, 1987).

Excerpt:

“Marsilius, whose chief work is entitled defender of the piece, was a Christian Aristotelian. But both his Christianity and his Aristotelianism differ profoundly from the beliefs of the most celebrated Christian Aristotelian, Thomas Aquinas. Marsilius lives as it were in another world than Thomas. In the whole defender he refers to Thomas only once, but even then, when he claims to quote Thomas, he infects quotes only the statements of another authoritative Christian writer which Thomas had asserted with that writers name in a compilation that he had made. Thomas had accepted the traditional ecclesiastical polity of the Roman church. Marsilius admits that the Christian priesthood is divinely established as distinct from the Christian laity, both being part of the Christian order; but he denies that the ecclesiastical hierarchy is divinely established. According to him all Christian priests are essentially equal in all respects as far as divine rights is concerned. He also denies that any priest, even if he be bishop or pope, has by divine right any of the following powers: the power to command or to coerce; the power to decide whether and how coercion is to be exercised against the apostates and heretics, be they subjects or princes; and the power to determine in a legally binding way which is Orthodox and what is heretical area and but we cannot go into Marsilius’s doctrine of the church although it was of the greatest political importance, especially during the Reformation, for that doctrine belongs to political theology rather than to political philosophy.”

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