History of Canon Law: Gratian, the Corpus Iuris Canonici and the Codes

Gratian’s Decretum (about 1140)

Britannica describes Gratian’s Decretum as a “collection of nearly 3,800 texts touching on all areas of church discipline and regulation,” “compiled by the Benedictine monk Gratian about 1140.” It calls Gratian “the father of the study of canon law.” The Decretum tried to reconcile conflicting older canons, and it became the main textbook in the medieval law schools.

The Corpus Iuris Canonici

Over the following centuries, papal collections of decretals were added to the Decretum. Together they formed the Corpus Iuris Canonici. Pope Gregory XIII approved an official text, and according to the Catholic Encyclopedia, “This edition of the ‘Corpus’ appeared at Rome in 1582” and “serves as exemplar for all subsequent editions.” In addition, the Council of Trent (Dec. 13, 1545, to Dec. 4, 1563) issued decrees that the Encyclopedia says “by themselves they form a short code.”

The 1917 Code

By the twentieth century, the law was scattered across many sources. Pope Benedict XV therefore promulgated the first Code of Canon Law on Pentecost Sunday, May 27, 1917. It took effect at Pentecost the following year, May 19, 1918, and replaced the Corpus Iuris Canonici.

The 1983 and 1990 Codes

After the Second Vatican Council, Pope John Paul II promulgated a revised Code on Jan. 25, 1983, effective the first Sunday of Advent, Nov. 27, 1983. Later, he promulgated the Code of Canons of the Eastern Churches on Oct. 18, 1990, effective Oct. 1, 1991. It has 1546 canons and applies to the Eastern Catholic Churches. See the 1983 Code of Canon Law.

Researching history of canon law in your state

To research history of canon law for a real matter, start with the primary sources. For example, read the statute, the rule and the documents in your own file. Then look for recent appellate decisions from your state, because they control how local courts read the law. After that, compare what you found with the federal rules that may also apply. Our state procedures guide and the Research Center can help you find and check each source.

Sources and further reading

Official sources used on this page:

• newadvent.org
• newadvent.org
• vatican.va
• vatican.va

Related reading on Lawtopolis:

• What Is Canon Law? Definition, Sources and Scope
• The 1983 Code of Canon Law: Structure and Key Canons
• Canon Law and the Western Legal Tradition