Definition
Lasione fidel (also rendered lœsione fidei or læsione fidei) is a Latin phrase meaning, literally, "injury to faith" or "wounding of faith." In ecclesiastical law, it referred to the jurisdiction claimed by church courts over breaches of promise or failures of conscience — particularly the non-payment of debts and violations of civil contracts — on the theory that breaking one's sworn word was a spiritual offense cognizable in a forum of conscience.
The concept operated as a doctrinal bridge by which ecclesiastical courts in medieval and early modern England attempted to assert jurisdiction over matters that were, at their core, civil disputes. The church courts argued that any breach of a solemn undertaking implicated the conscience and the soul, bringing it within their purview regardless of whether the underlying obligation was temporal in nature.
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Common Confusion
LASIONE FIDEL / LŒSIONE FIDEI / LŒSIO ENORMIS: The typographical corruption in Black's 2nd Edition ("LZESIONE FIDEL") may mislead researchers into thinking they are encountering an entirely different term. Additionally, lœsione fidei (injury to faith; breach of sworn promise) is frequently confused with lœsio enormis (injury from gross disproportion in contractual value under Roman law). The two share Latin roots and appear in overlapping ecclesiastical and Roman law sources, but they are conceptually distinct: lœsione fidei is about the moral wrong of breaking one's word; lœsio enormis is about the substantive unfairness of the bargain itself.
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Recognized Forms
/SUBTYPES
SUITS PRO LASIONE FIDEI: The formal procedural category — suits brought in ecclesiastical courts for spiritual offenses against conscience — encompassing non-payment of debts and breaches of civil contracts. These suits were the principal vehicle through which church courts asserted lœsione fidei jurisdiction. The attempt was ultimately curtailed by the common law courts through the writ of prohibition, which prevented ecclesiastical courts from entertaining suits that properly belonged to secular jurisdiction.
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Why It Matters in Research
This term surfaces almost exclusively in historical legal sources dealing with the jurisdictional conflicts between ecclesiastical and common law courts in England, primarily from the medieval period through the seventeenth century. Researchers working in this area face several navigational challenges.
First, spelling is highly inconsistent across sources. Black's 2nd Edition renders it "LZESIONE FIDEL" — an obvious typographical corruption of "lœsione fidei." You will encounter the term spelled variously as lœsione fidei, læsione fidei, lesione fidei, and lasione fidel across different editions and manuscript sources. Do not treat these as distinct terms; they are orthographic variants of the same concept. Search broadly.
Second, the term is inseparable from the history of ecclesiastical jurisdiction and the writ of prohibition. Any research into this concept must extend into sources on the prohibitio de laicis — the writs by which common law courts checked church court overreach. The two concepts are functionally paired in the historical literature.
Third, the doctrine has no modern operative relevance in Anglo-American law. Ecclesiastical court jurisdiction over civil debts and contracts was effectively eliminated centuries ago. The term appears in modern legal research almost exclusively in historical or comparative ecclesiastical law contexts, or in studies of the development of equity jurisdiction (since lœsione fidei suits were an early, contested analogue to equitable relief for breach of conscience).
Fourth, note the connection flagged in the Black's entry to Roman civil law: the concept of lœsio enormis (gross injury or disproportion in contract price) is a related but distinct Roman law doctrine cited alongside lœsione fidei in some sources. Do not conflate them. Lœsio enormis concerns the fairness of the contractual exchange; lœsione fidei concerns the breach of a sworn obligation.
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Historical Dictionary Support
Black's Law Dictionary (2nd Ed.) is the primary dictionary source for this term in the Law Mind corpus. The entry is fragmentary — the text as preserved reads as a partial definition — but it establishes two key points: (1) that suits pro lasione fidei were prosecuted in ecclesiastical courts for spiritual offenses against conscience, including non-payment of debts and breaches of civil contracts; and (2) that this "attempt to turn the ecclesiastical courts into courts of equity was checked" — the sentence breaks off, but the reference is to the common law courts' use of prohibition to restrain this jurisdiction.
The reference to Colquhoun's Roman Civil Law (§ 2094) in the adjacent text concerns lœsio enormis, not lœsione fidei proper — a reminder that historical dictionary entries frequently cluster related but distinct Roman and ecclesiastical law concepts in close proximity, requiring careful reading to separate them.
Historical dictionaries generally do not develop this term beyond brief mention. Researchers seeking substantive treatment should look to ecclesiastical legal history sources and treatments of the jurisdictional history of the English church courts rather than relying on dictionary entries alone.
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Jurisdictional Note
Lœsione fidei as an operative legal doctrine is specific to the historical jurisdiction of English ecclesiastical courts and has no direct counterpart in American law. In comparative ecclesiastical law contexts, canon law traditions in other jurisdictions may use related concepts, but the specific procedural history of suits pro lasione fidei belongs to English legal history.
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