A.T. Robertson Commentary Revelation 4:10

"the four and twenty elders shall fall down before him that sitteth on the throne, and shall worship him that liveth for ever and ever, and shall cast their crowns before the throne, saying," — Revelation 4:10 (ASV)

Shall fall down (πεσουντα, future middle of πιπτω),

shall worship (προσκυνησουσιν, future active of προσκυνεω),

shall cast their crowns (βαλουσιν τους στεφανους, future active of βαλλω). The two actions by the two groups (living creatures, elders) are coordinated (simultaneous in the repetition). They thus acknowledge that all this kingly dignity comes from God, who is King of kings and Lord of lords. Charles takes the elders, however, to be angels, not redeemed men.