Read Revelation 12:10-12. There is the song of victory sung in heaven. It will be sung by those who will have been caught up to heaven out OF "the great Tribulation." (Revelation 7; Revelation 14; and Revelation 15). When Satan is cast down, "he hath but a short time," which is definitely stated to be 3 1/2 years, during which he is wroth with the woman, and makes war with the remnant of her seed (Revelation 12:14-17).
At the first advent, the First Coming of The LORD Jesus Christ, the announcement was made "on earth, peace." But NOW, at the time of the Second Advent, it is "in heaven, WAR!"
In 2 Thessalonians 2, we find further information as to the rise of this final embodiment of Satanic power. There we are clearly told that the revelation of that awful being has an appointed season. He cannot arise before his time. Here, we are told why and how this is.
The time has come in the Divine counsels for this great event of the ages. Satan, who has hitherto had access to the heavens is at long last to be cast out.
Any intelligent spiritual student of the Bible should be ready to acknowledge that there MUST be a difference between the SAVING Gospel for the sinner and the EDIFYING Gospel for the saint.