A.T. Robertson Commentary Revelation 5:14

"And the four living creatures said, Amen. And the elders fell down and worshipped." — Revelation 5:14 (ASV)

Amen (Αμην). The four living creatures give their approval to the doxology after the antiphonal songs.

Fell down and worshipped (επεσαν κα προσεκυνησαν). In silent adoration that closes the whole service of praise to the One upon the throne and to the Lamb. As in 4:10 so here the representatives of the redeemed bow in silent worship. Pliny says that the Christians sing a song to Christ as to God. He is here worshipped by the universe (Php 2:10f.).