Canon Episcopi

The title canon Episcopi (also capitulum Episcopi) is conventionally given to a certain passage found in medieval canon law. The text possibly originates in an early 10th-century penitential, recorded by Regino of Prüm; it was included in Gratian's authoritative Corpus juris canonici of c. 1140 (Decretum Gratiani, causa 26, quaestio 5, canon 12) and as such became part of canon law during the High Middle Ages.

It is an important source on folk belief and surviving pagan customs in Francia on the eve of the formation of the Holy Roman Empire. The folk beliefs described in the text reflect the residue of pre-Christian beliefs at about one century after the Carolingian Empire had been Christianized. Its condemnation of the belief in witchcraft was an important argument used by the opponents of the witch trials during the 16th century, such as Johann Weyer.

The conventional title "canon Episcopi" is based on the text's incipit, and was current from at least the 17th century.

It is perhaps first attested in the Libri de synodalibus causis et disciplinis ecclesiasticis composed by Regino of Prüm around 906. It was included in Burchard of Worms' Decretum (compiled between 1008 and 1012), an early attempt at collecting all of Canon law

The text was adopted in the Decretum of Ivo of Chartres and eventually in Gratian's authoritative Corpus juris canonici of c. 1140 (causa 26, quaestio 5, canon 12). Because it was included in Gratian's compilation the text was treated as canon law for the remaining part of the High Middle Ages, until Roman Catholic views on European witchcraft began to change dramatically in the late medieval period. The text of Gratian is not the same as the one used by Burchard, and the distinctive features of the Corrector text were thus not transmitted to later times.

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