The scene now shifts back to earth. [source][source][source]
"The entire passage in every clause utilizes well known prophetic anticipations of the day of the Lord, and by his use of these images John identifies the day for his readers. One may check this by consulting the chief scriptures John employs, notably Joel 2:10; Joel 2:30 f, Isaiah 13:9 ff; Isaiah 2:10 ff; Isaiah 34:4,Ezekiel 32:7 f, Hosea 10:8. These passages depict the concomitants of the day of the Lord and supply John with all his pictures." [1][source]
The eschatological day of the Lord in prophecy includes a time of judgment (the Tribulation) followed by a time of blessing (the Millennium). [source][source][source]