Conclusion
Upon curing Petronella of Polesworth of epilepsy, Thomas Becket was described as a ‘good and faithful doctor’ (‘bonus et fidelis medicus’)®8 Before coming to Canterbury, Petronella had had no faith in earthly medicine, and yet Becket had been able to heal her, not because he was a good doctor but because he was a good andfaithful doctor.®9 This description is illustrative too of his cures of the possessed.
Not only could he cure their physical bodies from demonic torment, and expel the demons that had control over their minds, he also provided a spiritual cure by cleansing their tortured souls, and restoring them to Christian society.Demons on the other hand, isolated their victims from the rest of the Christian population by using their bodies to express non-human behaviour, such as roaming wild or blaspheming. Neither miracle collection contains a detailed “medical” explanation for madness, as William of Canterbury provided for epilepsy, yet demonic causes for madness appear alongside other explanations, including the punishment of sin and the instability of the mind. It is for this reason that demoniacs should not be excluded from studies of madness or from considerations of the influence of medical theories on ecclesiastical writers. Investigations of medieval madness have rightly moved on from Basil Clarke’s Mental Disorder in Earlier Britain (1975), in which he recommended
‘excluding demonic explanations’ from his survey of ‘the ramifications of medical thought on mental disorder’ because such explanations ‘do not feature in the main textbooks’.[1059] William of Canterbury’s portrayal of Thomas Becket as a doctor throughout his collection is illustrative of the association he made between medicine and healing. Sicknesses of the body were connected to sicknesses of the mind and soul because all three functioned together in a state of health. For some illnesses, earthly medicine was not enough; a spiritual cure was necessary and for this, one required a spiritual doctor.