Decretum Gratiani

The Decretum Gratiani or Concordia discordantium canonum (in some manuscripts Concordantia discordantium canonum) is a collection of Canon law compiled and written in the 12th century as a legal textbook by the jurist known as Gratian. It forms the first part of the collection of six legal texts, which together became known as the Corpus Juris Canonici. It retained legal force in the Roman Catholic Church until Pentecost 1918, when a revised Code of Canon Law (Codex Iuris Canonici) promulgated by Pope Benedict XV on 27 May 1917 obtained the Force of Law.