Adam Clarke's Commentary on the Bible - Acts 14:13
Then the priest of Jupiter, which was before their city - There is a meaning here, which ordinary readers will not readily apprehend. Many cities were put under the protection of a particular deity; and the image of that deity placed at the entrance, to signify that he was the guardian and protector. To this St. Luke, every where as accurate as he is circumstantial, refers. Lystra, it appears, was under the guardianship of Jupiter Propulaius, Διος προπυλαιου , which St. Luke translates, ... read more
Adam Clarke's Commentary on the Bible - Acts 14:12
They called Barnabas, Jupiter; and Paul, Mercurius - The heathens supposed that Jupiter and Mercury were the gods who most frequently assumed the human form; and Jupiter was accustomed to take Mercury with him on such expeditions. Jupiter was the supreme god of the heathens; and Mercury was by them considered the god of eloquence. And the ancient fable, from which I have quoted so largely above, represents Jupiter and Mercury coming to this very region, where they were entertained by Lycaon,... read more