I believe that key to rightly dividing the book of Revelation, is to recognise that the events recorded in this book can be broadly divided into two parallel blocks — chapters 4 through to 11 forming the first block, and chapters 12 through to 20 forming the second block. When one understands that these two blocks of Scripture are complementary in nature—that is, they run parallel to one another covering the same period of time in the Tribulation—one is then able to rightly divide the book of Revelation making sense of its chronology and the events that happen within it.
In this teaching, we endeavour to compare side-by-side, the trumpet judgments of Revelation 8, 9 and 11, with the vial judgments of chapter 16. In doing this, we discover that whilst there are slight discrepancies between the two accounts, the overwhelming similarities between the two necessitate that they are referring to the same event. Take a listen and decide for yourself.