Ecclesiastical Latin, also called Church Latin or Liturgical Latin, is a form of Latin developed to discuss Christian thought in late antiquity and used in Christian liturgy, theology, and church administration to the present day, especially in the Catholic Church. It includes words from Vulgar Latin and Classical Latin (as well as Greek and Hebrew) re-purposed with Christian meaning. It is less stylized and rigid in form than Classical Latin, sharing vocabulary, forms, and syntax, while at the same time incorporating informal elements which had always been with the language but which were excluded by the literary authors of Classical Latin.
Its pronunciation was partly standardized in the late 8th century during the Carolingian Renaissance as part of Charlemagne's educational reforms, and this new letter-by-letter pronunciation, used in France and England, was adopted in Iberia and Italy a couple of centuries afterwards. As time passed, pronunciation diverged depending on the local vernacular language, giving rise to even highly divergent forms such as the traditional English pronunciation of Latin, which has now been largely abandoned for reading Latin texts. Within the Catholic Church and in certain Protestant churches, such as the Anglican Church, a pronunciation based on modern Italian phonology, known as Italianate Latin, has become common since the late 19th century.
