The Elders round about the Throne must be representatives of the Old and New Testament Saints, that have been redeemed by the blood of Christ.

          They are seated on Thrones not ordinary seats, and remind us of  Daniel's Vision of the Judgment in Daniel 7:9-10. . .
"I beheld till the thrones were cast down, and the Ancient of days did sit, whose garment was white as snow, and the hair of his head like the pure wool: his throne was like the fiery flame, and his wheels as burning fire.
A fiery stream issued and came forth from before him: thousand thousands ministered unto him, and ten thousand times ten thousand stood before him: the judgment was set, and the books were opened."