1. Terminology and types
The term canon law designates the whole body of legal rules of the Catholic Church. Two types can be distinguished, the ius divinum on the one hand, and the ius mere ecclesiasticum or ius humanum on the other. The semantic root of the term canon law can be traced back to the Greek word κανών, which may be circumscribed as meaning ‘rule’ or ‘guide’. Linguistic usage within the church in late antiquity attributed this word (and its Latin counterpart canon) to every dogma claiming binding force; in that sense biblical writings considered to be authoritative by the church were termed canon. It is against this background that the description of the rules enacted by the early councils (like for instance the Nicene Council 325) as canons can be explained. However, the so-called ‘canonical collections’, certified since late antiquity, also designated other norms as canons. This is particularly true for papal letters, which decided a particular case with binding force or answered a particular question. Having recourse to the words decretum (decision, decree) and decretalis (depending on a decree), these kinds of papal norms based on individual cases, which emerged at the beginning of the 4th century, were named epistola decretalis or littera decretalis respectively. The expression ‘decretal’, which is usually used in academic literature, is based on these terms. In particular, the Constitution, which resembles secular laws with its abstract-general formulation, superseded the decretal since the 15th century; nowadays, the Constitution in the form of the Constitutio Apostolica constitutes the preferred method of papal law-making on matters of special importance. In contrast, ‘canon’ remained for a long time the characteristic term for counciliar rules. However, important councils in the early modern and modern periods such as the Council of Trent (1545–63) or Vatican II (1962–65) used the words ‘decretum’ or ‘constitution’ for their abstract-general rules. As an element of legal order the canon is still present in both codifications of the Catholic Church in force today, the Codex Iuris Canonici (in force since 1983) for the Roman Catholic Church and the Codex Canonum Ecclesiarum Orientalium for the 21 eastern Churches which have a law of their own.
2. Tendencies of historical development
The history of canon law is closely connected with the emergence and evolution of ecclesiastical structures and organization. In this respect three epochs can be distinguished: A first phase involves the period until the emergence of a church based on law (Rechtskirche), which had begun to rise under Pope Gregory VII (1073–85). The second period is characterized by a rapid development of legal rules for all ecclesiastical matters, accompanied by fierce contests with secular powers and the period of ecclesiastical crises caused by schism and the Reformation. The last period begins with the Council of Trent (1545–63) and lasts until the present day.
a) Origins and evolution of the church as an institution
Writings containing rules are already to be found in the Scriptures as in Paul’s Pastoral Epistles. Beginning with the onset of the 2nd century, early instances of legal normativity emerged in Episcopal letters like the first letter of the Roman bishop Clement to the parish in Corinth (around 96) or compilations of rules for the life in parishes like the Didache (around 100). The need for further rules increased since around the 2nd century, when organized entities governed by bishops evolved from the ancient Christian parishes. Initially, in particular educational letters of leading bishops like Cyprian of Carthage (d 258) or works of leading theologians like Tertullian (d after 220), later called ‘patristic works’, fulfilled this need for guidelines and rules. These patristic texts were to be an important source for ecclesiastical rule-making. This is demonstrated, for example, by the history of the right of Episcopal elections, whose textual and ideological roots can be found in Cyprian’s writings. Of increasing importance for ecclesiastical life, however, were counciliar canons, coming into existence in the 4th century, and the decretals of the Roman bishops, first documented in full in 385. This development is proven by the emergence of the already-mentioned canonical collections. In part widespread throughout Europe—as for instance the Collectio Dionysiana, compiled around the year 500 in Rome by Dionysius Exiguus, or the Collectio Isidori Mercatoris, created in 9th century France—these textual collections guaranteed the steady presence of ecclesiastical rules in the collective memory of Christendom. So, the collections accompanied the emergence of an Episcopal jurisdiction at the diocesan level (since the 9th century) and the evolution of the ecclesiastical hierarchy, which ranged from bishops to Metropolitans and Patriarchs and further on up to the Roman bishop, even though his claim to primacy was still contested in this period (schism of 1054 between the Roman and the Byzantine Church).
b) Rise of the church based on law (Rechtskirche) in the period between the pontificate of Gregory VII (1073–85) and the opening of the Council of Trent (1545)
From the middle of the 11th century, legal normativity appeared to attain more and more importance in ecclesiastical discourse. The binding force of decreta et statuta sanctorum patrum (the decrees and statutes of the holy fathers) was particularly emphasized by Gregory VII time and again. This corresponded to the rapid increase in the numbers of canonical collections during this period. The rising interest in law and legal structures is also mirrored by the efforts of compilers like bishop Burchard of Worms (d 1025) or bishop Ivo of Chartres (d 1115) to create collections which featured a more systematic ordering of the compiled texts. In particular, the increase of papal law-making and the papal claim to govern the church by means of legal devices inspired the thesis of a ‘papal revolution’ (Berman). This might be exaggerated. But actually the papacy of the 12th, 13th and 14th centuries transformed the church into an institution essentially defined by law. Through the extensive issuing of decretals and in cooperation, in particular, with the four Lateran councils of 1123, 1139, 1179 and 1215 which had been gathered by the papacy, all areas of ecclesiastical practice became shaped by law. In particular, marriage and criminal law developed into extensive fields regulated by canon law. This process was supported by the evolution of the new science of canon law (ius commune). Its rise was due to a number of different factors: the triumph of scholastic jurisprudence, the spread of academic education in theology, but also the 12th and particularly 13th-century advancement of Roman law; these factors, combined with the expanding ambit of church jurisdiction on the diocesan level and in the shape of papal ‘judges delegate’, fostered the emergence of professionalized jurists. The university-trained ecclesiastical jurists occupied leading positions within the church and frequently advanced to its highest levels as demonstrated by the careers of popes such as Innocent IV (1243–54), who wrote one of the most influential contemporary commentaries on canon law.
The starting point for the markedly scientific version of canon law of this period—also called the ‘age of classical canon law’—was set by the Concordia Discordantium Canonum, created around 1140 by Gratian, teacher of law in Bologna. This work, also named Decretum Gratiani, included—as did former canonical collections—a selection of canons, decretals and other texts such as excerpts of patristic scriptures. Its strong impact and wide distribution across Europe was based on its systematic order and analytical quality, which was unique in the tradition of canon law collections up to that point. The sheer size of Gratian’s collection alone with its nearly 4,000 capitula turned it into a monumental store of ecclesiastical legal memory. However, first and foremost, Gratian had been able to form the abundant multiplicity of texts into a reasonably harmonious system using accompanying comments (dicta) and a very advanced systematic order. With his law book, the use of traditional texts in legal science and ecclesiastical legal practice was considerably facilitated. It was characteristic of Gratian’s method, guided by scholasticism, that his decretum soon obtained the status of legally binding rules, which, for their part, became the object of jurisprudential analysis: beginning in the late 12th century, a decretistic legal science emerged, which, inspired by the techniques developed by the glossators, dealing with the corpus of Roman law (ius commune), commented on individual words or passages of Gratian’s decretum. With Johannes Teutonicus’ (d 1245) commentary, which was subsequently used as a main reference, similar to the Glossa ordinaria, the rise of decretistic jurisprudence reached its peak. Of even greater prominence were the ‘decretalists’ who focused on the post-Gratian papal ius novum, as it was generally called. Committed to the goal of collecting and analysing those texts which were not included in the Decretum Gratiani and which were thus called Extravagantes (extra decretum vagantes), decretalists like Bernardus Papiensis (d 1213) created decretal collections. Of these, the so-called Compilationes Antiquae, created 1188/90–1226, were to become particularly widely read.
It is telling of the decretalists’ significance for the papacy that one of these compilations—the Compilatio Tertia (1209/10)—was initiated by Innocent III (1198–1216) in order to highlight papal power concerning textual form and systematic order of decretal law. The promulgation of the so-called Liber Extra by Gregory IX (1227–41) followed a similar line. This papal law book included nearly 2,000 legal rules mainly of the period 1140–1234, whose textual form was given an abstract-general orientation as a result of intense editorial work. Only in this new format were the texts of the Liber Extra authorized for use in courts and in scholis (in the universities). To some extent, this reveals a kind of codifying approach, which became even stronger in the Liber Sextus, promulgated by Boniface VIII (1294–1303) in 1298: composed as a collection of already existing legal norms from the period between 1234 and 1298, the Liber Sextus gave only scant evidence of the origin of its decretals in individual cases; instead, these texts were transformed into abstract rules. At the same time, all legal provisions of the period after 1234, which had not been included in the Liber Sextus, were denied authoritativeness.
It was typical of the dynamics of canon law discourse that decretalists commented on the Liber Extra and Liber Sextus with the same intensity as they did on the Constitutiones Clementinae, the collection of legal texts of Pope Clement V (1305–14) and the council of Vienne (1311/1312). However, by the time the Clementinae were promulgated by John XXII (1316–34) in 1317, the Church dominated by the Pope had come to a turning point in its history. In the course of the contests for supremacy during the 12th and 13th centuries in Europe, the papacy had been able to defend its claim against the competing secular powers, especially against the Staufen Emperors. The canon lawyers had supported the papacy in its attempt to use legal interpretations for the promotion of political authority and fostered papal rights in relation to the Emperor; at some point, the canonists even argued along the lines of papa est verus imperator (see the Summa Parisiensis, 1160/70, and the Summa Coloniensis, 1169). These ideas found their culmination in 1302 when Boniface VIII claimed supreme power over the whole world; tellingly, the Pope referred to an interpretation of the doctrine of the two swords, which was intensely debated by the canonists (stating that secular power, symbolized by the secular sword, received its legitimacy by papal power, symbolized by the ecclesiastical sword). However, Boniface’s arrest by the French king in 1303, the subordination of the papacy to the French monarchy for a period of time—symbolized by curial residence in Avignon 1309–76—and, above all else, the Great Schism from 1378 onwards (witnessing the contest between two and, beginning in 1409, even three papal pretenders) created grave crises for the church. However, in overcoming the schism, the impact and formative power of the canon law tradition proved crucial: it was the argument that the Pope should merely act as an ecclesiastical organ, which had been developed in canon law debates since the late 12th century, that offered a legal basis for the idea of counciliar supremacy and thus opened the way to end the schism by electing Martin V (1417–31) as Pope at the Council of Constance (1414–18). Implicitly, the normative power of canon law revealed itself also in the Reformation period which began in 1517: even though the Reformators strongly opposed traditional ecclesiastical structures, numerous Church ordinances revealed obvious continuities from canon law as in the field of ecclesiastical service, disciplinary law or rights of patronate.
c) Consolidation and codification: the period since the Council of Trent (1545–63)
With the Counter-Reformation, initiated by the Council of Trent and its efforts to strengthen ecclesiastical discipline and the powers of the episcopate and papacy, canon law also became the object of efforts for reform: in 1580 Gregory XIII (1572–85) declared the authoritativeness of an edition, established by the so-called Correctores Romani, of the Decretum Gratiani, Liber Extra, Liber Sextus, Clementinae as well as the Extravagantes Johannis XXII and the Extravagantes Communes, originally compiled by the Parisian canonist Jean Chappuis. Together with its main commentaries (the respective Glossa ordinaria) these texts represented as Corpus Iuris Canonici the essential textual basis of canon law until 1918, even though other legal rules also kept their binding force. This way, the medieval canon law tradition shaped the practice and jurisprudence of the modern Roman Catholic Church. Early modern canon lawyers adopted the traditional exegesis of individual texts in the order of their disposal, as for example Prosperus Fagnanus (1588−1678) in his commentary on the decretals, published in 1661. But under the influence of humanism, the systematic and cross-textual analysis of legal institutions gained more weight, as in the works of Enricus Pirhing (1606–79) and Zegerus Bernardus van Espen (1646–1728). They developed a systematic structure different to the prevailing legal order of former canon law.
It was only at the beginning of the 20th century that the Roman Catholic Church moved on to codifying its laws (codification): promulgated in 1917 by Benedict XV (1914–22) the Codex Iuris Canonici came into force in 1918. In its four books shaped by the system of the German Bürgerliches Gesetzbuch (BGB) (the first book dealt with the normae generales similar to the ‘general part’ in the German code) and the institutional order of Roman law, the new code of the Church adopted mainly the older tradition of regulation. The Codex Iuris Canonici, promulgated in 1983 by John Paul II (1978–2005) constitutes a more marked turning point, as is illustrated by the second of its seven books De populo Dei, where the theological impact of Vatican II is evident. Nevertheless, the older legal tradition is still alive and represents with the traditio canonica an explicitly accepted device of dogmatic analysis.
3. Canon law and European private law tradition
Canon law has strongly influenced parts of the European tradition of private law. This is obvious in the law of marriage. The idea of marriage as a monogamous relation between man and woman, which gave rise to mutual obligations to support each other and which could be dissolved only in special cases, had become the dominant model of regulation since the 12th century at the latest and also provided the model for the national codifications. The law of contracts, too, has been shaped in essential points by the discourse within canon law. This is in particular true for the freedom of the parties to conclude contracts without any attention to specific types or formal regulations. The principle pacta sunt servanda has its textual roots in the decision of the Council of Carthage 345/348 and the arguments of the decretist Huguccio of Pisa (d 1210), who stressed the binding force of promises. On the other side, it was Huguccio’s and others’ idea quod fides non est ei servanda qui frangit fidem (faith is not to be kept vis-à-vis a person who has broken faith) which paved the way for the idea of termination of a contract for non-performance in the European tradition of contract law. Canon law’s prohibition of interest (prohibition of usury) provides another good example. Rudimentarily conceived in the first Nicene council, the principle was significantly further developed in the 12th century before encountering increasing criticism from the 13th century onwards, and its influence on the contract law discourse in Europe has been considerable. Similarly, the prohibition against usury also strongly influenced contractual practice as the European centres of banking, in particular, routinely attempted to circumvent the prohibition. In property law the doctrine of acquisitive prescription adopted elements of the canon law tradition.
Moreover, canon law and European private law are linked by the history of rule-making mechanisms and their normative structures. The combination of collection, systematization and analytical abstraction, in particular in the age of classical canon law, is a distinct example of the emergence of a European culture of knowledge under the conditions of a multiplicity of heterogeneous legal texts. The Regulae Iuris, adopted 1298 in the Liber Sextus, pay testimony to the rise and impact of legislatively enacted ‘principles of law’. Last but not least, these elements make the history of canon law a point of reference for the developmental dynamics of modern European private law.
Literature and Sources
For a survey of the history of classical canon law see Wilfried Hartmann and Kenneth Pennington (eds), The History of Medieval Canon Law in the Classical Period, 1140–1234: From Gratian to the Decretals of Pope Gregory IX (2008); for a shorter survey see the respective articles on the topic in Stanley N Katz (ed), The Oxford International Encyclopedia of Legal History, vol 1 (2009), 293–6, 353–7; vol 2, 316–19, 385–7; vol 4, 351–5. An excellent survey of Medieval canon law is provided by James A Brundage, Medieval Canon Law (1995) and Richard H Helmholz, The Spirit of Classical Canon Law (1996, 2010). The texts of the Corpus Iuris Canonici are available in the editions by Aemilius (Emil) Friedberg, Corpus Iuris Canonici, Editio Lipsiensis secunda; Pars prior: Decretum Magistri Gratiani; Pars secunda: Decretalium Collectiones (1879–81, reprinted 2000); partial translation of the Decretum Gratiani and the Glossa Ordinaria by Augustine Thompson and James Gordley, The Treatise on Laws (1994); for the pre-Gratian sources see Lotte Kéry, Canonical Collections of the Early Middle Ages (ca 400–1140). A Bibliographical Guide to Manuscripts and Literature (1999).