Final answer:
The original language of Haec dies is Latin.
Step-by-step explanation:
The original language of Haec dies is Latin.
Latin was the language of the educated elite in Europe, even after it faded as a spoken language. Written communication, such as the Bible, was still conducted in Latin, allowing educated individuals from different countries to correspond with each other.
Latin is part of the Romance Language Group, which includes languages like French, Italian, and Spanish.