The history of the word PAGAN is an interesting example of how the language changes over time to suit the needs of society.
PAGAN comes from the same source as the word ‘peasant’. The Latin word pagus referred to a stick fixed in the ground as a landmark and came to also refer to the surrounding area of countryside. Paganus came to mean ‘country-dweller’. This meaning shifted to ‘civilian’ and its opposite was miles or ‘soldier’.
When the Christians began to call themselves milites, meaning ‘enlisted soldiers of Christ’, paganus shifted its meaning to refer to a non-Christian. HEATHEN had a similar change, originally meaning ‘someone who lived on the heath’ or ‘an inhabitant of the wild country’. It followed the same pattern as PAGAN, coming to denote a non-Christian.
The words still have this meaning but over time they have broadened to include non-Jews as well as non-Christians.
The meaning continues to change and both words are now used in the wider sense of someone who holds no religious beliefs.