Oecumenius
He poured out the bowl upon the air. And a voice said: “It is done.” What is done? Clearly, the commandment of God and His will.
When it was said from heaven, “It is done,” there came lightning and voices. The lightning was from above, while the voices belonged to those on earth who were frightened by the lightning.
There were also thunders and an earthquake. By earthquake John means the disturbance of the earth, since it is named among the signs of the end of the world.
Or by earthquake he means the change of visible things, according to the word of Haggai: “Once more I will shake not only heaven, but also earth, sea, and dry land, and I will shake all nations” (Hag 2:6-7).
For this reason he also indicates that nothing like it had happened before.