MERCURY stands in the AV for the Gr. Hermes in Ac 14:12. Hermes, as the spokesman of the gods, was regarded by the Greeks as the god of eloquence. Hence, when Paul and Barnabas healed the cripple at Lystra, the former was hailed as Hermes, 'because he was the chief speaker.' The identification of Hermes with Mercury was due to another attribute. As the messenger of the gods, Hermes was the god who brought good fortune to men. Mercury was the Roman god of commerce (cf. merx, mercari), and success in commerce was attributed to him. Hence the mythology of the two was confused.

A. E. Hillard.