Canon law

The law of the Roman Catholic and Eastern Orthodox churches. A canon is a rule adopted by a council; these canons formed the foundation of canon law. (From Greek kanon, for rule or measure).

In the Western church, the canons of the councils were supplemented with decrees of the Popes, which were gathered together into collections called decretals.

In the twentieth century, attempts were made to codify canon law, which two millennia of development had left quite a mess. The first code of canon law was published in 1917. An revised code was published in 1983.