Jesus was confronted by the leadership within Jerusalem during the last week of his earthly ministry (Matthew 21-23). He confounded the elders, scribes (teachers), chief priests, Pharisees, and Sadducees. He pronounced eight (8) woes on the scribes and Pharisees and called them a brood of vipers. He told the leaders of Jerusalem that judgment for the righteous bloodshed from all those on earth would be cast upon that last generation in Judea living during the first century AD (Matthew 23:36; 24:34). It would include their killing the Messiah as they filled up the measure of their guilt (Matthew 23:32). Their temple had already been declared desolate (Matthew 23:38). That Great Tribulation was recorded from heaven's perspective on a scroll (Matthew 24:21). John was allowed to record his view of those scenes for us in chapters 6-11 of The Revelation of Jesus the Christ within Heaven. They're discussed here. They historically verified Jesus's pronouncements. The last seven were announced with trumpets to show Jesus used His power from the Throne of God (Revelation 11:17).