From Ernst Kantorowicz’s magisterial The King’s Two Bodies:
Godfrey of Fontaines, a Belgian philosopher of the late thirteenth century, for example, succeeded in integrating very neatly the corpus mysticum into the Aristotelian scheme. To him the “mystical body” appeared not as a supra-natural foundation, but as a gift of nature. His major premise was that “everyone is [by nature] part of a social community, and thereby also a member of some mystical body.” That is, man is “by nature” a social animal; as an animal sociale, however, man is “by nature”–not “by grace”–also part of some mystical body, some social collective or aggregate, which Dante, a little while later, would easily define as “mankind” or humana civilitas, whereas others might define it, as need be, in the sense of populus, civitas, regnum, or patria, or as any other social community and corporation, the ends of which were “moral” per se. 
Contemporary secular political theory no doubt will consider the idea of civic society as a mystical body ill-shaped. But then, the contemporary age is one where an atomized metaphysics holds sway: in our secular age, the only reality is that which can be quantified. Yet if formal and final causality are real, as common sense affirms, then our age is deeply mistaken. And also if they are real, then Godfrey seems to be on to something. Human sociality is not a mere artefact of human volition; rather, it is an artefact of divine volition, folded into our essence from day one.