A.T. Robertson Commentary Revelation 16:17

"And the seventh poured out his bowl upon the air; and there came forth a great voice out of the temple, from the throne, saying, It is done:" — Revelation 16:17 (ASV)

Upon the air (επ τον αερα). All men breathe the air and this is worse than the smiting of the earth (verse 2), the sea (3), the fresh waters (4), the sun (8).

A great voice (φωνη μεγαλη). The voice of God as in 16:1.It is done (Γεγονεν). Perfect active indicative of γινομα. Like Γεγοναν in 21:6. The whole series of plagues is now complete.