The word occurs in the NT only in connexion with Herod Agrippa, who, at Caesarea, ‘made an oration’ (δημηγορέω) from the throne (or judgment-seat [Revised Version margin]) to the embassy from Tyre and Sidon (Acts 12:21). It refers to set speeches made in public assemblies, but sometimes it is employed in a derogatory sense for speeches of the demagogic order. There is a curious use of the word in the Septuagint , Proverbs 30:31 (Proverbs 28:27)-βασιλεὺς δημηγορῶν ἐν ἔθνει. It was not an unusual thing for kings and princes to make orations in public assembly.
John Reid.