John Wesley on Revelation 6:12

And I saw - This sixth seal seems particularly to point out God's judgment on the wicked departed. St. John saw how the end of the world was even then set before those unhappy spirits. This representation might be made to them, without anything of it being perceived upon earth. The like representation is made in heaven, Rev 11:18. And there was a great earthquake - Or shaking, not of the earth only, but the heavens. This is a farther description of the representation made to those unhappy souls.