The question debated among medieval political theorists was not whether Christendom was a body, ultimately the body of Christ, but whether there was room for more than one “head” of the body. As Otto Gierke summarizes,”Mankind constituted a Mystical Body, whereof the Head was Christ. It was just from this principle that theorists of the ecclesiastical party deduced the proposition that upon earth the Vicar of Christ represents the one and only Head of this Mystical Body, for, were the Emperor an additional Head, we should have before us a two-headed monster, an animal biceps. Starting from the same pictorial concept, the theorists of the imperial party inferred the necessity of a Temporal head of Christendom, since there must needs be a separate Head for each of those two organisms which together constitute the one Body. The ultimate Unity of this Body, they argued, was preserved by the existence of its Heavenly Head, for, though it be true that the body mystical, like the body natural, cannot end in two heads, still there is exactly this difference between the two cases, namely, that in the mystical body under its one Supreme Head there may be parts which themselves are complete bodies, each with a head of its own.”
Peter Leithart
Peter J. Leithart is President of Theopolis Institute. He is the author of numerous books on theology, literature, and culture, including Theopolitan, Defending Constantine, and Baptized Body.
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