A.T. Robertson Commentary Revelation 11:16

"And the four and twenty elders, who sit before God on their thrones, fell upon their faces and worshipped God," — Revelation 11:16 (ASV)

The four and twenty elders (ο εικοσ τεσσαρες πρεσβυτερο). They follow the living creatures (verse 15, if correctly interpreted) in their adoration, as in 4:9f.. Though seated on thrones of their own (4:4), yet they fall upon their faces in every act of worship to God and Christ (4:10; 5:8,14; 19:4). Here επ τα προσωπα αυτων (upon their faces) is added as in 7:11 about the angels. The elders here again represent the redeemed, as the four living creatures the forces of nature, in the great thanksgiving here (ευχαριστουμεν, present active indicative of ευχαριστεω).