Jerome's Latin translation of the Bible, known as the Vulgate and completed in stages around the turn of the fifth century, became the standard biblical text of Western Christianity for over a thousand years, shaping Catholic theological vocabulary so thoroughly that many core Latin theological terms passed largely unchanged into English and other European languages through it.
The Council of Trent in the sixteenth century formally declared the Vulgate authoritative for Catholic doctrine and liturgy, cementing a status it had already held informally for centuries, and Catholic biblical scholarship continued to reference and revise the Vulgate text, including a major twentieth century revision, well after other confessions had shifted toward translations from the original Hebrew and Greek. Latin was also the working language of Western scholastic theology, the systematic method of argument, definition, and disputation developed in medieval universities and applied most influentially by Thomas Aquinas in works including the Summa Theologica, which addressed questions ranging from the nature of God to the ethics of everyday conduct using a rigorous Latin technical vocabulary largely built for the purpose. This shared Latin scholarly language let theologians across different countries engage directly with each other's arguments without translation, producing a genuinely international medieval intellectual culture organized around Latin universities. Scholastic Latin terminology, including concepts such as substance, accident, and the several senses distinguished for scriptural interpretation, remains part of the working vocabulary of Catholic theology today, even in discussions conducted primarily in modern languages.