"This misunderstanding is based on an inadequate understanding of medieval Latin. In classical Latin, perfidus did have a meaning similar to its present English analogue, derived as it was from the phrase per fidem decipere, “to deceive through trust.” However, by late antiquity and the early Middle Ages, perfidus and perfidia simply meant the opposite of fides and fidelis. (K.P. Harrington, Mediaeval Latin (1925), p. 181, fn 5) Thus perfidus in medieval Latin is best translated as “faithless” or “unbelieving”, meaning lacking the Christian faith."
en.wikipedia.org/wiki/Good_Friday_Prayer_for_the_Jews#cite_note-10
Yes, I was already aware of that footnote from Wikipedia, which slightly mischaracterizes the text it references. It does not, however, seem to be particularly borne out by other sources. The dictionaries and glossaries I have checked do not reflect such a meaning, and those include the
Oxford (mostly class.),
Lewis & Short (incl. post-class. and med.),
Dict. of Ecclesiastical Latin,
Cassel’s,
Riddle and Arnold, the
Revised Medieval Latin Word-List (ironically, giving “very faithful” as a possible meaning), and the
Glossarium Mediae et Infimae Latinitatis. The fact is, it is
infidelis or
incredulus, not
perfidus, that generally means “unbelieving.”
The best that can be said is that the situation is substantially more complicated than merely saying, “
perfidus in medieval Latin is best translated as ‘faithless’ or ‘unbelieving’, meaning lacking the Christian faith.” Notwithstanding the facile-sounding claims about Bede and other late-Latin writers which are made in the book to which you are referring, rather to the contrary:
Augustine of Hippo employed
perfidus with particular frequency in his treatise against the Donatist bishop Petilianus, where he rejected the rebaptism of those unknowingly baptized by ‘faithless’ priests. In this context,
perfidus, while retaining strong connotations of betrayal, had come to characterize those who remained obdurately separate from the catholic church, whether through false belief or apostasy.
The word seems to have retained these dual overtones in the seventh century; for Isidore
perfidus could be defined as ‘deceitful’ (
fraudulentus) and lacking in faith. For Bede, a century later, it carried a complex nexus of associations. As among the African Fathers, while still strongly associated with treachery, it was used principally in the context of betrayal of, or violent hostility to, the Christian faith. That is apparent in the
Historia Ecclesiastica, in which, besides the two references to the British already mentioned,
perfidia and its compounds occur 11 times. In four cases the word is connected with heresy – it is the quality ascribes to the doctrines of Arius and Pelagius, to those who sell the sacraments and to heretics in general. In four others it is applied to those whom Bede thought of as apostates, that is, to Insular rulers who tried to overthrow the Christian religion as established by their predecessors. In the remaining three it is used to distinguish pagans who persecuted or violently attacked catholic Christians: Roman officials in Britain, Saracens in Gaul, King Penda of Mercia. In the
Historia Ecclesiastica, then, Bede’s use of
perfidia does not extend beyond the enemies and persecutors of the church. And in the later books at least it is mostly confined to persecutors of the nascent English church.
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